Hierarchical porous carbon material(MMC)was successfully fabricated via hard template synthesis method by carbonization of furfury alcohol within the template(MCM-41).The prepared MMC was studied with characterization...Hierarchical porous carbon material(MMC)was successfully fabricated via hard template synthesis method by carbonization of furfury alcohol within the template(MCM-41).The prepared MMC was studied with characterization methods including scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption analyses,and infrared spectral analysis(FTIR).To investigate kinetics of toluene adsorption of hierarchical porous carbon materials,the adsorption performances of these carbon samples with varying pore structure(MC-1,MMC,MMHPC)were analyzed via dynamic adsorption.And the Langmuir model and Freundlich equation were employed to correspond with adsorption isotherms to study the adsorption mechanism.The experimental results demonstrate that the Langmuir model is more appropriate to describe the adsorption process.The capacities of toluene adsorption follow the order of MMC<MMHPC(micro-meso hierarchical porous carbon)<MC-1(microporous carbon).MC-1 has satisfactory absorption performance due to its large pore volume and high ratio of micropores.MMHPC has excellent toluene adsorption performance for proper amounts of surface oxygen containing groups.Long saturation time,interconnected hierarchical pore channels,and large specific surface area make MMC also a promising material for VOCs treatment.These data reveal that the pore channel structure,rational pore distribution,high surface area and reasonable amounts of surface oxygen groups are the main factors contributed to excellent toluene adsorption performance,which proposes theoretical basis for hierarchical porous carbon materials to further engineering application.展开更多
It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical ...It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical porous carbons with good combination of micro and meso-porous architecture derived from a new oxygen-bridged porous organic polymer(OPOP).The OPOP is produced by the condensation polymerization of cyanuric chloride and hydroquinone in NaOH ethanol solution and NaCl is in-situ formed as by-product that will serve as template to construct an interconnected 3D hierarchical porous architecture upon carbonization.The large interface pore architecture,and rich doping of N and O heteroatoms effectively promote the electrolyte accessibility and electronic conductivity,and provide abundant active sites for energy storage.Consequently,the supercapacitors based on the optimized OPOP-800 sample display an energy density of 8.44 and 27.28 Wh·kg^(−1)in 6.0 M KOH and 1.0 M Na2SO4 electrolytes,respectively.The capacitance retention is more than 94%after 10,000 cycles.Furthermore,density functional theory(DFT)calculations have been employed to unveil the charge storage mechanism in the OPOP-800.The results presented in this job are inspiring in finely tuning the porous structure to optimize the supercapacitive performance of carbon materials.展开更多
Lithium-selenium(Li-Se)batteries have attracted considerable attentions for next-generation energy storage systems owing to high volumetric capacity of 3265 m Ah cm^(-3) and excellent electronic conductivity(~10^(-5)S...Lithium-selenium(Li-Se)batteries have attracted considerable attentions for next-generation energy storage systems owing to high volumetric capacity of 3265 m Ah cm^(-3) and excellent electronic conductivity(~10^(-5)S cm^(-1))of selenium.However,the shuttling effect and capacity fading prevent their wide applications.Herein we report a low-cost strategy for scalable fabrication of lignin derived hierarchical porous carbon(LHPC)as a new high-loading Se host for high-capacity and long-term cycling Li-Se batteries in carbonate electrolyte.The resulting LHPC exhibits three-dimensional(3D)hierarchically porous structure,high specific surface area of 1696 m^(2) g^(-1),and hetero-atom doping(O,S),which can effectively confine the Se particles into the micropores,and meanwhile,offer effective chemical binding sites for selenides from hetero-atoms(O,S).As a result,our Li-Se batteries based on Se@LHPC demonstrate high capacity of 450 m Ah g^(-1) at 0.5 C after 500 cycles,with a low capacity fading rate of only 0.027%.The theoretical simulation confirmed the strong affinity of selenides on the O and S sites of LHPC effectively mitigating the Se losing.Therefore,our strategy of using lignin as the low-cost precursor of hierarchically porous carbon for high-loading Se host offers new opportunities for high-capacity and long-life Li-Se batteries.展开更多
Lithium-sulfur(Li-S)batteries,although a promising candidate of next-generation energy storage devices,are hindered by some bottlenecks in their roadmap toward commercialization.The key challenges include solving the ...Lithium-sulfur(Li-S)batteries,although a promising candidate of next-generation energy storage devices,are hindered by some bottlenecks in their roadmap toward commercialization.The key challenges include solving the issues such as low utilization of active materials,poor cyclic stability,poor rate performance,and unsatisfactory Coulombic efficiency due to the inherent poor electrical and ionic conductivity of sulfur and its discharged products(e.g.,Li2S2 and Li_(2)S),dissolution and migration of polysulfide ions in the electrolyte,unstable solid electrolyte interphase and dendritic growth on an odes,and volume change in both cathodes and anodes.Owing to the high specific surface area,pore volume,low density,good chemical stability,and particularly multimodal pore sizes,hierarchical porous carbon(HPC)mate rials have received considerable attention for circumventing the above pro blems in Li-S batteries.Herein,recent progress made in the synthetic methods and deployment of HPC materials for various components including sulfur cathodes,separators and interlayers,and lithium anodes in Li-S batteries is presented and summarized.More importantly,the correlation between the structures(pore volume,specific surface area,degree of pores,and heteroatom-doping)of HPC and the electrochemical performances of Li-S batteries is elaborated.Finally,a discussion on the challenges and future perspectives associated with HPCs for Li-S batteries is provided.展开更多
Large surface area,high conductivity,and rich active site of carbon electrode materials are necessary characteristics for energy storage devices.However,high conductivity and high nitrogen doping of carbon electrode m...Large surface area,high conductivity,and rich active site of carbon electrode materials are necessary characteristics for energy storage devices.However,high conductivity and high nitrogen doping of carbon electrode materials are difficult to coordinate.Here,a facile method via the carbonization of nitrogen-containing Schiff base polymer has been developed to prepare high conductivity and high nitrogen-doped hierarchical porous carbon.The organic components with a benzene ring structure in the polymer promote the formation of more sp^(2)-graphitized carbon,which is beneficial for the improvement of electrical conductivity.Nitrogen-doped hierarchical porous carbon calcined at 900℃ under the NH3 atmosphere possesses high nitrogen content of 7.48 at%,a large specific surface area of 1613.2m2/g,and high electrical conductivity of 2.7 S/cm.As electrode materials in an aqueous-based supercapacitor,nitrogen-doped hierarchical porous carbon exhibits superior specific capacitance of 385 F/g at 1 A/g as well as excellent rate performance(242 and 215 F/g at a current density of 100 and 200 A/g,respectively).In addition,the specific capacitance of electrode measured in a two-electrode system is 335 F/g at 1 A/g,and the long-term cycling stability can be achieved with more than 94%initial capacitance after 10000 cycles.The constructed symmetric supercapacitor delivers high energy density and high power density.The outstanding electrochemical performances combined with the novel and scalable synthetic approach make the nitrogen‐doped hierarchical porous carbon potential electrode material for electrochemical devices.展开更多
By utilizing hard template method to adjust the mesopore length, and alkali activation to generate micro pores, two hierarchical porous carbons(HPCs) were prepared. With controlling of their mesopore length and the ac...By utilizing hard template method to adjust the mesopore length, and alkali activation to generate micro pores, two hierarchical porous carbons(HPCs) were prepared. With controlling of their mesopore length and the activation conditions, the complex system composed by HPCs and electrolyte was simplified and the effect of mesopore length on the performance of HPCs as electrodes in supercapacitors was investi gated. It is found that with the mesopore length getting smaller, the ordered area gets smaller and th aggregation occurs, which is caused by the high surface energy of small grains. HPC with long pore(HPCL) exhibits a donut-like morphology with well-defined ordered mesopores and a regular orientation while in HPC with short pores(HPCS), short mesopores are only orderly distributed in small regions Longer ordered channels form unobstructed ways for ions transport in the particles while shorter chan nels, only orderly distributed in small areas, results in blocked paths, which may hinder the electrolyt ions transport. Due to the unobstructed structure, HPCL exhibits good rate capability with a capacitanc retention rate over 86% as current density increasing from 50 m A/g to 1000 m A/g. The specific capaci tance of HPCL derived from the cyclic voltammetry test at 10 m V/s is up to 201.72 F/g, while the specifi capacitance of HPCS is only 193.65 F/g.展开更多
Room temperature sodium-sulfur(RT Na-S)batteries are gaining extensive attention as attractive alternatives for large-scale energy storage,due to low cost and high abundancy of sodium and sulfur in nature.However,the ...Room temperature sodium-sulfur(RT Na-S)batteries are gaining extensive attention as attractive alternatives for large-scale energy storage,due to low cost and high abundancy of sodium and sulfur in nature.However,the dilemmas regarding soluble polysulfides(Na_(2)Sn,4<n<8)and the inferior reaction kinetics limit their practical application.To address these issues,we report the activated porous carbon fibers(APCF)with small sulfur molecules(S2-4)confined in ultramicropores,to achieve a reversible single-step reaction in RT Na-S batteries.The mechanism is investigated by the in situ UV/vis spectroscopy,which demonstrates Na2S is the only product during the whole discharge process.Moreover,the hierarchical carbon structure can enhance areal sulfur loading without sacrificing the capacity due to thorough contact between electrolyte and sulfur electrode.As a consequence,the APCF electrode with 38 wt%sulfur(APCF-38S)delivers a high initial reversible specific capacity of 1412 mAh g^(-1) and 10.6mAh cm^(-2)(avg.areal sulfur loading:7.5 mg cm^(-2))at 0.1 C(1C=1675 mA g^(-1)),revealing high degree of sulfur utilization.This study provides a new strategy for the development of high areal capacity RT Na-S batteries.展开更多
Developing host materials with high specific surface area, good electron conductivity, and fast ion transportation channel is critical for high performance lithium-selenium(Li-Se) batteries. Herein, a series of three ...Developing host materials with high specific surface area, good electron conductivity, and fast ion transportation channel is critical for high performance lithium-selenium(Li-Se) batteries. Herein, a series of three dimensional ordered hierarchically porous carbon(3D OHPC) materials with micro/meso/macropores are designed and synthesized for Li-Se battery. The porous structure is tuned by following the concept of the generalized Murray’s law to facilitate the mass diffusion and reduce ion transport resistance.The optimized 3D Se/OHPC cathode exhibits a very high 2 nd discharge capacity of 651 m Ah/g and retains 361 m Ah/g after 200 cycles at 0.2 C. Even at a high current rate of 5 C, the battery still shows a discharge capacity as high as 155 m Ah/g. The improved electrochemical performance is attributed to the synergy effect of the interconnected and well-designed micro, meso and macroporosity while shortened ions diffusion pathways of such Murray materials accelerate its ionic and electronic conductivities leading to the enhanced electrochemical reaction. The diffusivity coefficient in Se/OHPC can reach a very high value of 1.3 × 10^(-11)cm^(2)/s, much higher than those in single pore size carbon hosts. Their effective volume expansion accommodation capability and reduced dissolution of polyselenides ensure the high stability of the battery. This work, for the first time, established the clear relationship between textural properties of cathode materials and their performance and demonstrates that the concept of the generalized Murray’s law can be used as efficient guidance for the rational design and synthesis of advanced hierarchically porous materials and the great potential of 3D OHPC materials as a practical high performance cathode material for Li-Se batteries.展开更多
Self-aggregation and sluggish transport kinetics of cathode materials would usually lead to the poor electrochemical performance for aqueous zinc-ion batteries(AZIBs).In this work,we report the construction of C@VO_(2...Self-aggregation and sluggish transport kinetics of cathode materials would usually lead to the poor electrochemical performance for aqueous zinc-ion batteries(AZIBs).In this work,we report the construction of C@VO_(2) composite via anti-aggregation growth and hierarchical porous carbon encapsulation.Both of the morphology of composite and pore structure of carbon layer can be regulated by tuning the adding amount of glucose.When acting as cathode applied for AZIBs,the C@VO_(2)-3:3 composite can deliver a high capacity of 281 m Ah g^(-1) at 0.2 A g^(-1).Moreover,such cathode also exhibits a remarkably rate capability and cyclic stability,which can release a specific capacity of 195 m Ah g^(-1) at 5 A g^(-1) with the capacity retention of 95.4%after 1000 cycles.Besides that,the evolution including the crystal structure,valence state and transport kinetics upon cycling were also deeply investigated.In conclusion,benefited from the synergistic effect of anti-aggregation morphology and hierarchical porous carbon encapsulation,the building of such C@VO_(2) composite can be highly expected to enhance the ion accessible site,boost the transport kinetics and thus performing a superior storage performance.Such design concept can be applied for other kinds of electrode materials and accelerating the development of highperformance AZIBs.展开更多
The hierarchical porous N/O co-functionalized carbon(HPNOC)was scalably prepared by using the lowcost and renewable blighted grains as the raw material coupled with mild KHCO_3 activation for electrochemical capacitor...The hierarchical porous N/O co-functionalized carbon(HPNOC)was scalably prepared by using the lowcost and renewable blighted grains as the raw material coupled with mild KHCO_3 activation for electrochemical capacitors(ECs).The elemental N was in situ doped in the obtained HPNOC without any N-containing additives.Remarkably,the obtained HPNOC was endowed with a large specific surface area(about 2 624m^2·g^(-1)),high pore volume(about 1.35cm^3·g^(-1)),as well as high-content N/O functionalization(about 1.9%(in atom)N and about 10.2%(in atom)O.Furthermore,the as-resulted HPNOC electrode with a high mass loading of 5mg·cm^(-2 )exhibited competitive gravimetric capacitances of about 373.6F·g^(-1 )at 0.5A·g^(-1),and even about 260.4F·g^(-1 )at a high rate of 10A·g^(-1);superior capacitance retention of about 98.8%at 1A·g^(-1 )over 10 000consecutive cycles;and high specific energy of about 9.6W·h·kg^(-1 )at a power of 500W·kg^(-1),when evaluated as a promising electrode in 6mol KOH for advanced electrochemical supercapacitors.More encouragingly,the green synthetic strategy we developed holds a huge promise in generalizing for other biomass-derived carbon materials for versatile energy-related applications.展开更多
Used as high-performance electrodes,both structural and compositional alterations of carbon materials play very important roles in energy conversion/storage devices.Especially in supercapacitors,hierarchical pores and...Used as high-performance electrodes,both structural and compositional alterations of carbon materials play very important roles in energy conversion/storage devices.Especially in supercapacitors,hierarchical pores and heteroatom doping in carbon materials are indispensable.Here the rambutan-like hierarchically porous carbon microspheres(PCMs)have been constructed via a hydrothermal treatment,followed by carbonization/activation.The hierarchically porous microstructure is composed of three-dimensional porous carbon networks,which give rise to a large surface area.Moreover,N and O functional groups are introduced in the as-prepared samples,which could generate the extra pseudocapacitance.Benefitting from the interconnected hierarchical and open structure,PCM exhibits outstanding capacitive performance,for example,superior specific capacitance and rate capability(397 and 288 F g^(−1) at 0.5 and 20A g^(−1),respectively),as well as long cycling stability(about 95%capacitance retention after 10,000 cycles).These encouraging results may pave an efficient way to fabricate advanced supercapacitors in the future.展开更多
Limited lithium resources have promoted the exploration of new battery technologies.Among them,potassium-ion batteries are considered as promising alternatives.At present,commercial graphite and other carbon-based mat...Limited lithium resources have promoted the exploration of new battery technologies.Among them,potassium-ion batteries are considered as promising alternatives.At present,commercial graphite and other carbon-based materials have shown good prospects as anodes for potassium-ion batteries.However,the volume expansion and structural collapse caused by periodic K+insertion/extraction have severely restricted further development and application of potassium-ion batteries.A hollow biomass carbon ball(NOP-PB)ternarily doped with N,O,and P was synthesized and used as the negative electrode of a potassium-ion battery.X-ray photoelectron spectroscopy,Fourier‐transform infrared spectroscopy,and transmission electron microscopy confirmed that the hollow biomass carbon spheres were successfully doped with N,O,and P.Further analysis proved that N,O,and P ternary doping expands the interlayer distance of the graphite surface and introduces more defect sites.DFT calculations simultaneously proved that the K adsorption energy of the doped structure is greatly improved.The solid hollow hierarchical porous structure buffers the volume expansion of the potassium insertion process,maintains the original structure after a long cycle and promotes the transfer of potassium ions and electrons.Therefore,the NOP‐PB negative electrode shows extremely enhanced electrochemical performance,including high specific capacity,excellent long‐term stability,and good rate stability.展开更多
Fossil fuel exhaustion and overdevelopment usually lead to a recession,which is worsened by the environmental pollution.So it is of high priority to develop high-efficiency energy storage device.Here,agreen and enviro...Fossil fuel exhaustion and overdevelopment usually lead to a recession,which is worsened by the environmental pollution.So it is of high priority to develop high-efficiency energy storage device.Here,agreen and environment-friendly strategy is devised to fabricate carbon materials from biomass.By water extraction and alcohol precipitation,polysaccharide is extracted from loquat leaves.After calcining under high temperature,hierarchical porous carbon materials(HPCM)are obtained,possessing a variety of macropores,mesopores and micropores.Such ample and hierarchical pores enable the electrolyte infiltration and the buffering of the volume expansion of sulfur in repeated electrochemical reactions.The structure stability of the entire electrode can thus be well maintained.When evaluated as the scaffold for sulfur,the electrochemical performance of carbon/sulfur composite was tested.Even after 500 cycles,the reversible capacity is retained as high as 485.4 mA·h/g at the current density of 1.6 A/g.It also offers a notable rate capability,attaining the discharge capacity of 700.7 mA·h/g at 2 C.All the electrochemical performance results prove the feasibility of the proposed strategy.展开更多
Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environ...Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and conversion.Herein,we report a general and simple zinc salts-assisted method for the synthesis of HPCs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and wastes.During the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in carbons.The prepared HPCs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size distributions.Moreover,the zinc salts can be recovered and recycled,supporting the sustainable production of HPCs on large scale.The prepared HPCs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.展开更多
Sodium fulvic acid based hierarchical porous carbons(SFA-HPCs) with a specific surface area of 1919 m^2·g^(–1) and total volume of 1.7 cm^3·g^(–1) has been synthesized by a simple self-template method. The...Sodium fulvic acid based hierarchical porous carbons(SFA-HPCs) with a specific surface area of 1919 m^2·g^(–1) and total volume of 1.7 cm^3·g^(–1) has been synthesized by a simple self-template method. The carbon skeleton can be formatted by the decomposition process of sodium fulvic acid(SFA) in a N_2 atmosphere. The sodium compund in SFA is used as a self-template to create the hierarchical porous structure. The unique hierarchical structure of SFA-HPCs provides an efficient pathway for electrolyte ions to be diffused into the internal surfaces of bulk electrode particles. It results in a high charge storage capacitance of 186 F·g^(–1) at current load of 40 A·g^(–1). The capacitance of 230 F·g^(–1) at 0.05 A·g^(–1) and 186 F·g^(–1) at 40 A·g^(–1) show its good rate capability. Besides, it also achieves desirable cycling stability, 99.4% capacitance remained after 10000 cycles at 40 A·g^(–1).展开更多
Wood-based bilayer solar evaporators,which possess cooperative advantages of natural wood and photothermal conversion coating including fast water transportation,low heat conduction,renewability,and high light absorba...Wood-based bilayer solar evaporators,which possess cooperative advantages of natural wood and photothermal conversion coating including fast water transportation,low heat conduction,renewability,and high light absorbability,hold great promise for water purification.However,previous studies suffer from low evaporation rates and high cost of coatings,and lack a deep understanding how the porous structures of coating layer function.Herein,a novel bilayer solar evaporator is designed through facile surface coating of wood by low-cost porous carbon from controlled carbonization of polyester waste.The porous carbon bears rich oxygen-containing groups,well-controlled micro-/meso-/macropores,and high surface areas(1164 m^(2) g^(−1)).It is proved that porous carbon improves sunlight absorption and promotes the formation of numerous water clusters to reduce water evaporation enthalpy.Owing to these combined features,the bilayer solar evaporator exhibits high evaporation rate(2.38 kg m^(−2) h^(−1)),excellent longterm stability,and good salt resistance.More importantly,a large-scale solar desalination device for outdoor experiments is developed to produce freshwater from seawater.The daily freshwater production amount(3.65 kg m^(−2))per unit area meets the daily water consumption requirement of one adult.These findings will inspire new paradigms toward developing efficient solar steaming technologies for desalination to address global freshwater shortage.展开更多
Porous carbon has been applied for lithium-sulfur battery cathodes,and carbonized metal-organic framework(MOF)is advantageous in tuning the morphology.Herein,we have systematically synthesized water-distorted MOF(WDM)...Porous carbon has been applied for lithium-sulfur battery cathodes,and carbonized metal-organic framework(MOF)is advantageous in tuning the morphology.Herein,we have systematically synthesized water-distorted MOF(WDM)derived porous carbon via controlling the proportion of both water in a mixed solvent(dimethylformamide and water)and ligand in MOF-5 precursors(metal and ligand),which is categorized by its morphology(i.e.Cracked stone(closed),Tassel(open)and Intermediate(semi-open)).For example,decrease in water and increase in ligand content induce Cracked stone WDMs which showed the highest specific surface area(2742-2990 m^(2)/g)and pore volume(2.81-3.28 cm^(3)/g)after carbonization.Morphological effect of carbonized WDMs(CWDMs)on battery performance was examined by introducing electrolytes with different sulfur reduction mechanisms(i.e.DOL/DME and ACN_(2) LiTFSITTE):Closed framework effectively confines polysulfide,whereas open framework enhances electrolyte accessibility.The initial capacities of the batteries were in the following order:Cracked stone>Intermediate>Tassel for DOL/DME and Intermediate>Tassel>Cracked stone for ACN_(2) LiTFSI-TTE.To note,Intermediate CWDM exhibited the highest initial capacity and retained capacity after 100 cycles(1398 and 747 mAh/g)in ACN_(2) LiTFSI-TTE electrolyte having advantages from both open and closed frameworks.In sum,we could correlate cathode morphology(openness and pore structure)and electrolyte type(i.e.polysulfide solubility)with lithium-sulfur battery performance.展开更多
The novel and facile preparation of magnetically interconnected micro/macroporous structure of monolithic porous carbon adsorbent(MPCA)were designed and presented herein.The synthesis was achieved via conventional fre...The novel and facile preparation of magnetically interconnected micro/macroporous structure of monolithic porous carbon adsorbent(MPCA)were designed and presented herein.The synthesis was achieved via conventional freezedrying and pyrolysis processes.In this study,sodium alginate and wasted black liquor were employed as starting precursors.Sodium alginate acts as a template of materials,whereas black liquor,the wasted product from the paper industry with plentiful of lignin content and alkaline solution,played an essential role in the reinforcement and activation of porosity for the resulting materials.Moreover,both the precursors were well dissolved in Fe^(3+) solution,providing a simple addition of a magnetic source in a one-pot synthesis.The interconnected micro/macroporous structures were generated through freeze-drying and,subsequently the pyrolysis process.The obtained cylindricalshaped monolithic porous carbon adsorbent(MPCA-700)showed high mechanical stability,a high BET specific surface area(902 m^(2)/g).Such aforementioned features were considered suitable to make the synthesized monolith as an adsorbent for the removal of heavy metal ions.The maximum adsorption capacity of MPCA-700 towards Pb^(2+) ions was 76.34 mg/g at pH 5.The adsorption studies illustrated that adsorption kinetics and isotherm perfectly fitted with the pseudo-second-order kinetics model and Langmuir isotherm,respectively.This work presents a promising protocol to reduce the overall costs in the preparation of renewable adsorbents with good adsorption efficiency and regeneration.展开更多
The Li-ion capacitors(LICs)develop rapidly due to their double-high features of high-energy density and high-power density.However,the relative low capacity of cathode and sluggish kinetics of anode seriously impede t...The Li-ion capacitors(LICs)develop rapidly due to their double-high features of high-energy density and high-power density.However,the relative low capacity of cathode and sluggish kinetics of anode seriously impede the development of LICs.Herein,the precisely pore-engineered and heteroatomtailored defective hierarchical porous carbons(DHPCs)as large-capacity cathode and high-rate anode to construct high-performance dual-carbon LICs have been developed.The DHPCs are prepared based on triple-activation mechanisms by direct pyrolysis of sustainable lignin with urea to generate the interconnected hierarchical porous structure and plentiful heteroatominduced defects.Benefiting from these advanced merits,DHPCs show the well-matched high capacity and fast kinetics of both cathode and anode,exhibiting large capacities,superior rate capability and long-term lifespan.Both experimental and computational results demonstrate the strong synergistic effect of pore and dopants for Li storage.Consequently,the assembled dual-carbon LIC exhibits high voltage of 4.5 V,high-energy density of 208 Wh kg^(−1),ultrahigh power density of 53.4 kW kg^(−1)and almost zerodecrement cycling lifetime.Impressively,the full device with high mass loading of 9.4 mg cm^(−2)on cathode still outputs high-energy density of 187 Wh kg^(−1),demonstrative of their potential as electrode materials for high-performance electrochemical devices.展开更多
A robust three-dimensional(3D)interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries.Herein,cellulose-based 3D hierarchical porous carbon(HPC)and two-dimen...A robust three-dimensional(3D)interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries.Herein,cellulose-based 3D hierarchical porous carbon(HPC)and two-dimensional(2D)lamellar porous carbon(LPC)are employed as the sulfur host and polysulfide-proof inter-layer,respectively,for a Li–S battery.The 3D HPC displays a cross-linked macroporous structure,which allows high sulfur loading and restriction capability and provides unobstructed electrolyte diffusion channels.With a stackable carbon sheet of 2D LPC that has a large plane view size and is ultrathin and porous,the LPC-coated separator effectively inhibits polysulfides.An optimized combination of the HPC and LPC yields an electrode structure that effectively protects the lithium anode against corrosion by polysulfides,giving the cell a high ca-pacity of 1339.4 mAh g^(-1) and high stability,with a capacity decay rate of 0.021% per cycle at 0.2C.This work provides a new understanding of biomaterials and offers a novel strategy to improve the performance of Li–S batteries for practical applications.展开更多
基金Funded by the National Program on Key Research Project of China(No.2016YFC1402406)。
文摘Hierarchical porous carbon material(MMC)was successfully fabricated via hard template synthesis method by carbonization of furfury alcohol within the template(MCM-41).The prepared MMC was studied with characterization methods including scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption analyses,and infrared spectral analysis(FTIR).To investigate kinetics of toluene adsorption of hierarchical porous carbon materials,the adsorption performances of these carbon samples with varying pore structure(MC-1,MMC,MMHPC)were analyzed via dynamic adsorption.And the Langmuir model and Freundlich equation were employed to correspond with adsorption isotherms to study the adsorption mechanism.The experimental results demonstrate that the Langmuir model is more appropriate to describe the adsorption process.The capacities of toluene adsorption follow the order of MMC<MMHPC(micro-meso hierarchical porous carbon)<MC-1(microporous carbon).MC-1 has satisfactory absorption performance due to its large pore volume and high ratio of micropores.MMHPC has excellent toluene adsorption performance for proper amounts of surface oxygen containing groups.Long saturation time,interconnected hierarchical pore channels,and large specific surface area make MMC also a promising material for VOCs treatment.These data reveal that the pore channel structure,rational pore distribution,high surface area and reasonable amounts of surface oxygen groups are the main factors contributed to excellent toluene adsorption performance,which proposes theoretical basis for hierarchical porous carbon materials to further engineering application.
基金the National Natural Science Foundation of China(No.21805235)China Postdoctoral Science Foundation(No.2017M610502)+2 种基金the Opening Foundation of Creative Platform of the Key Laboratory of the Education Department of Hunan Province(No.20K131)the Construct Program of the Key Discipline in Hunan Province is greatly acknowledged.H.C.and Z.G.L.thank the support from the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20170817110251498)Shenzhen Key Laboratory of Interfacial Science and Engineering of Materials(No.ZDSYS20200421111401738).
文摘It is a big challenge to well control the porous structure of carbon materials for supercapacitor application.Herein,a simple in-situ self-templating strategy is developed to prepare three-dimensional(3D)hierarchical porous carbons with good combination of micro and meso-porous architecture derived from a new oxygen-bridged porous organic polymer(OPOP).The OPOP is produced by the condensation polymerization of cyanuric chloride and hydroquinone in NaOH ethanol solution and NaCl is in-situ formed as by-product that will serve as template to construct an interconnected 3D hierarchical porous architecture upon carbonization.The large interface pore architecture,and rich doping of N and O heteroatoms effectively promote the electrolyte accessibility and electronic conductivity,and provide abundant active sites for energy storage.Consequently,the supercapacitors based on the optimized OPOP-800 sample display an energy density of 8.44 and 27.28 Wh·kg^(−1)in 6.0 M KOH and 1.0 M Na2SO4 electrolytes,respectively.The capacitance retention is more than 94%after 10,000 cycles.Furthermore,density functional theory(DFT)calculations have been employed to unveil the charge storage mechanism in the OPOP-800.The results presented in this job are inspiring in finely tuning the porous structure to optimize the supercapacitive performance of carbon materials.
基金financially supported by the National Key R&D Program of China(Grants 2016YBF0100100,2016YFA0200200)the National Natural Science Foundation of China(Grants 51872283,21805273)+1 种基金the Liaoning Bai Qian Wan Talents Program,Natural Science Foundation of Liaoning Province,Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(Grant 20180510038)the Liao Ning Revitalization Talents Program(Grant XLYC1807153),DICP(DICP ZZBS201708,DICP ZZBS201802,DICP I202032),DNL Cooperation Fund,CAS(DNL180310,DNL180308,DNL201912,and DNL201915),DICP&QIBEBT(Grant DICP&QIBEBT UN201702)。
文摘Lithium-selenium(Li-Se)batteries have attracted considerable attentions for next-generation energy storage systems owing to high volumetric capacity of 3265 m Ah cm^(-3) and excellent electronic conductivity(~10^(-5)S cm^(-1))of selenium.However,the shuttling effect and capacity fading prevent their wide applications.Herein we report a low-cost strategy for scalable fabrication of lignin derived hierarchical porous carbon(LHPC)as a new high-loading Se host for high-capacity and long-term cycling Li-Se batteries in carbonate electrolyte.The resulting LHPC exhibits three-dimensional(3D)hierarchically porous structure,high specific surface area of 1696 m^(2) g^(-1),and hetero-atom doping(O,S),which can effectively confine the Se particles into the micropores,and meanwhile,offer effective chemical binding sites for selenides from hetero-atoms(O,S).As a result,our Li-Se batteries based on Se@LHPC demonstrate high capacity of 450 m Ah g^(-1) at 0.5 C after 500 cycles,with a low capacity fading rate of only 0.027%.The theoretical simulation confirmed the strong affinity of selenides on the O and S sites of LHPC effectively mitigating the Se losing.Therefore,our strategy of using lignin as the low-cost precursor of hierarchically porous carbon for high-loading Se host offers new opportunities for high-capacity and long-life Li-Se batteries.
基金Yinyu Xiang is very grateful to the China Scholarship Council(CSC:No.201806950083)for his PhD scholarship。
文摘Lithium-sulfur(Li-S)batteries,although a promising candidate of next-generation energy storage devices,are hindered by some bottlenecks in their roadmap toward commercialization.The key challenges include solving the issues such as low utilization of active materials,poor cyclic stability,poor rate performance,and unsatisfactory Coulombic efficiency due to the inherent poor electrical and ionic conductivity of sulfur and its discharged products(e.g.,Li2S2 and Li_(2)S),dissolution and migration of polysulfide ions in the electrolyte,unstable solid electrolyte interphase and dendritic growth on an odes,and volume change in both cathodes and anodes.Owing to the high specific surface area,pore volume,low density,good chemical stability,and particularly multimodal pore sizes,hierarchical porous carbon(HPC)mate rials have received considerable attention for circumventing the above pro blems in Li-S batteries.Herein,recent progress made in the synthetic methods and deployment of HPC materials for various components including sulfur cathodes,separators and interlayers,and lithium anodes in Li-S batteries is presented and summarized.More importantly,the correlation between the structures(pore volume,specific surface area,degree of pores,and heteroatom-doping)of HPC and the electrochemical performances of Li-S batteries is elaborated.Finally,a discussion on the challenges and future perspectives associated with HPCs for Li-S batteries is provided.
基金Peng Wang and Xiaohuan Qi contributed equally to this study.This study was supported by the National Key Research and Development Program(Grant No.2016YFB0901600)National Natural Science Foundation of China(Grant Nos.21801247,51672295,51972326,and 21871008)the Key Research Program of Frontier Chinese Academy of Sciences(Grant No.QYZDJ-SSW-JSC013).
文摘Large surface area,high conductivity,and rich active site of carbon electrode materials are necessary characteristics for energy storage devices.However,high conductivity and high nitrogen doping of carbon electrode materials are difficult to coordinate.Here,a facile method via the carbonization of nitrogen-containing Schiff base polymer has been developed to prepare high conductivity and high nitrogen-doped hierarchical porous carbon.The organic components with a benzene ring structure in the polymer promote the formation of more sp^(2)-graphitized carbon,which is beneficial for the improvement of electrical conductivity.Nitrogen-doped hierarchical porous carbon calcined at 900℃ under the NH3 atmosphere possesses high nitrogen content of 7.48 at%,a large specific surface area of 1613.2m2/g,and high electrical conductivity of 2.7 S/cm.As electrode materials in an aqueous-based supercapacitor,nitrogen-doped hierarchical porous carbon exhibits superior specific capacitance of 385 F/g at 1 A/g as well as excellent rate performance(242 and 215 F/g at a current density of 100 and 200 A/g,respectively).In addition,the specific capacitance of electrode measured in a two-electrode system is 335 F/g at 1 A/g,and the long-term cycling stability can be achieved with more than 94%initial capacitance after 10000 cycles.The constructed symmetric supercapacitor delivers high energy density and high power density.The outstanding electrochemical performances combined with the novel and scalable synthetic approach make the nitrogen‐doped hierarchical porous carbon potential electrode material for electrochemical devices.
基金financial support from the Natural Science Foundation of China(no.51177156/E0712)
文摘By utilizing hard template method to adjust the mesopore length, and alkali activation to generate micro pores, two hierarchical porous carbons(HPCs) were prepared. With controlling of their mesopore length and the activation conditions, the complex system composed by HPCs and electrolyte was simplified and the effect of mesopore length on the performance of HPCs as electrodes in supercapacitors was investi gated. It is found that with the mesopore length getting smaller, the ordered area gets smaller and th aggregation occurs, which is caused by the high surface energy of small grains. HPC with long pore(HPCL) exhibits a donut-like morphology with well-defined ordered mesopores and a regular orientation while in HPC with short pores(HPCS), short mesopores are only orderly distributed in small regions Longer ordered channels form unobstructed ways for ions transport in the particles while shorter chan nels, only orderly distributed in small areas, results in blocked paths, which may hinder the electrolyt ions transport. Due to the unobstructed structure, HPCL exhibits good rate capability with a capacitanc retention rate over 86% as current density increasing from 50 m A/g to 1000 m A/g. The specific capaci tance of HPCL derived from the cyclic voltammetry test at 10 m V/s is up to 201.72 F/g, while the specifi capacitance of HPCS is only 193.65 F/g.
基金Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20170036National Natural Science Foundation of China,Grant/Award Numbers:51572129,51772154,51811530100+1 种基金the Materials Characterization Facility of Nanjing University of Science and Technology for XRD,SEM,and TEM experiments.This study was supported by National Natural Science Foundation of China(Nos.51572129,51772154,and 51811530100)Natural Science Foundation of Jiangsu Province(No.BK20170036).
文摘Room temperature sodium-sulfur(RT Na-S)batteries are gaining extensive attention as attractive alternatives for large-scale energy storage,due to low cost and high abundancy of sodium and sulfur in nature.However,the dilemmas regarding soluble polysulfides(Na_(2)Sn,4<n<8)and the inferior reaction kinetics limit their practical application.To address these issues,we report the activated porous carbon fibers(APCF)with small sulfur molecules(S2-4)confined in ultramicropores,to achieve a reversible single-step reaction in RT Na-S batteries.The mechanism is investigated by the in situ UV/vis spectroscopy,which demonstrates Na2S is the only product during the whole discharge process.Moreover,the hierarchical carbon structure can enhance areal sulfur loading without sacrificing the capacity due to thorough contact between electrolyte and sulfur electrode.As a consequence,the APCF electrode with 38 wt%sulfur(APCF-38S)delivers a high initial reversible specific capacity of 1412 mAh g^(-1) and 10.6mAh cm^(-2)(avg.areal sulfur loading:7.5 mg cm^(-2))at 0.1 C(1C=1675 mA g^(-1)),revealing high degree of sulfur utilization.This study provides a new strategy for the development of high areal capacity RT Na-S batteries.
基金financial support from the China Scholarship Council (CSC) and a scholarship from the Laboratory of Inorganic Materials Chemistry,Universitéde Namur,Belgiumfinancially supported by the National Postdoctoral Program (Grant No. 2020M672782)+2 种基金the National Natural Science Foundation of China (Grant No. U1663225)the the Program of Introducing Talents of Discipline to Universities-National 111 Project from the Ministry of Science and Technology and the Ministry of Education of China (Grant No. B20002)the National Key R&D Program of China (Grant No. 2016YFA0202602)。
文摘Developing host materials with high specific surface area, good electron conductivity, and fast ion transportation channel is critical for high performance lithium-selenium(Li-Se) batteries. Herein, a series of three dimensional ordered hierarchically porous carbon(3D OHPC) materials with micro/meso/macropores are designed and synthesized for Li-Se battery. The porous structure is tuned by following the concept of the generalized Murray’s law to facilitate the mass diffusion and reduce ion transport resistance.The optimized 3D Se/OHPC cathode exhibits a very high 2 nd discharge capacity of 651 m Ah/g and retains 361 m Ah/g after 200 cycles at 0.2 C. Even at a high current rate of 5 C, the battery still shows a discharge capacity as high as 155 m Ah/g. The improved electrochemical performance is attributed to the synergy effect of the interconnected and well-designed micro, meso and macroporosity while shortened ions diffusion pathways of such Murray materials accelerate its ionic and electronic conductivities leading to the enhanced electrochemical reaction. The diffusivity coefficient in Se/OHPC can reach a very high value of 1.3 × 10^(-11)cm^(2)/s, much higher than those in single pore size carbon hosts. Their effective volume expansion accommodation capability and reduced dissolution of polyselenides ensure the high stability of the battery. This work, for the first time, established the clear relationship between textural properties of cathode materials and their performance and demonstrates that the concept of the generalized Murray’s law can be used as efficient guidance for the rational design and synthesis of advanced hierarchically porous materials and the great potential of 3D OHPC materials as a practical high performance cathode material for Li-Se batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.51774203)the Shenzhen Science and Technology Program(Nos.JCYJ20200109105801725)。
文摘Self-aggregation and sluggish transport kinetics of cathode materials would usually lead to the poor electrochemical performance for aqueous zinc-ion batteries(AZIBs).In this work,we report the construction of C@VO_(2) composite via anti-aggregation growth and hierarchical porous carbon encapsulation.Both of the morphology of composite and pore structure of carbon layer can be regulated by tuning the adding amount of glucose.When acting as cathode applied for AZIBs,the C@VO_(2)-3:3 composite can deliver a high capacity of 281 m Ah g^(-1) at 0.2 A g^(-1).Moreover,such cathode also exhibits a remarkably rate capability and cyclic stability,which can release a specific capacity of 195 m Ah g^(-1) at 5 A g^(-1) with the capacity retention of 95.4%after 1000 cycles.Besides that,the evolution including the crystal structure,valence state and transport kinetics upon cycling were also deeply investigated.In conclusion,benefited from the synergistic effect of anti-aggregation morphology and hierarchical porous carbon encapsulation,the building of such C@VO_(2) composite can be highly expected to enhance the ion accessible site,boost the transport kinetics and thus performing a superior storage performance.Such design concept can be applied for other kinds of electrode materials and accelerating the development of highperformance AZIBs.
基金supported by the National Natural Science Foundations of China(Nos.51572005,51772127)
文摘The hierarchical porous N/O co-functionalized carbon(HPNOC)was scalably prepared by using the lowcost and renewable blighted grains as the raw material coupled with mild KHCO_3 activation for electrochemical capacitors(ECs).The elemental N was in situ doped in the obtained HPNOC without any N-containing additives.Remarkably,the obtained HPNOC was endowed with a large specific surface area(about 2 624m^2·g^(-1)),high pore volume(about 1.35cm^3·g^(-1)),as well as high-content N/O functionalization(about 1.9%(in atom)N and about 10.2%(in atom)O.Furthermore,the as-resulted HPNOC electrode with a high mass loading of 5mg·cm^(-2 )exhibited competitive gravimetric capacitances of about 373.6F·g^(-1 )at 0.5A·g^(-1),and even about 260.4F·g^(-1 )at a high rate of 10A·g^(-1);superior capacitance retention of about 98.8%at 1A·g^(-1 )over 10 000consecutive cycles;and high specific energy of about 9.6W·h·kg^(-1 )at a power of 500W·kg^(-1),when evaluated as a promising electrode in 6mol KOH for advanced electrochemical supercapacitors.More encouragingly,the green synthetic strategy we developed holds a huge promise in generalizing for other biomass-derived carbon materials for versatile energy-related applications.
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China(Grant Nos.21965007,51671062,and 51871065)the Guangxi Natural Science Foundation(Grant No.2018GXNSFFA281005)+1 种基金the Scientific Research and Technology Development Program of Guangxi(Grant Nos.AA19182014 and AA17202030-1)Guangxi Bagui Scholar Foundation,Guangxi Advanced Functional Materials Foundation and Application Talents Small Highlands,and Chinesisch-Deutsche Kooperationsgruppe(Grant No.GZ1528).
文摘Used as high-performance electrodes,both structural and compositional alterations of carbon materials play very important roles in energy conversion/storage devices.Especially in supercapacitors,hierarchical pores and heteroatom doping in carbon materials are indispensable.Here the rambutan-like hierarchically porous carbon microspheres(PCMs)have been constructed via a hydrothermal treatment,followed by carbonization/activation.The hierarchically porous microstructure is composed of three-dimensional porous carbon networks,which give rise to a large surface area.Moreover,N and O functional groups are introduced in the as-prepared samples,which could generate the extra pseudocapacitance.Benefitting from the interconnected hierarchical and open structure,PCM exhibits outstanding capacitive performance,for example,superior specific capacitance and rate capability(397 and 288 F g^(−1) at 0.5 and 20A g^(−1),respectively),as well as long cycling stability(about 95%capacitance retention after 10,000 cycles).These encouraging results may pave an efficient way to fabricate advanced supercapacitors in the future.
基金The authors are grateful for support from the National Natural Science Foundation of China(No.21671160).
文摘Limited lithium resources have promoted the exploration of new battery technologies.Among them,potassium-ion batteries are considered as promising alternatives.At present,commercial graphite and other carbon-based materials have shown good prospects as anodes for potassium-ion batteries.However,the volume expansion and structural collapse caused by periodic K+insertion/extraction have severely restricted further development and application of potassium-ion batteries.A hollow biomass carbon ball(NOP-PB)ternarily doped with N,O,and P was synthesized and used as the negative electrode of a potassium-ion battery.X-ray photoelectron spectroscopy,Fourier‐transform infrared spectroscopy,and transmission electron microscopy confirmed that the hollow biomass carbon spheres were successfully doped with N,O,and P.Further analysis proved that N,O,and P ternary doping expands the interlayer distance of the graphite surface and introduces more defect sites.DFT calculations simultaneously proved that the K adsorption energy of the doped structure is greatly improved.The solid hollow hierarchical porous structure buffers the volume expansion of the potassium insertion process,maintains the original structure after a long cycle and promotes the transfer of potassium ions and electrons.Therefore,the NOP‐PB negative electrode shows extremely enhanced electrochemical performance,including high specific capacity,excellent long‐term stability,and good rate stability.
基金supported by the Fundamental Research Funds of Shandong University(No.2016JC033)the Taishan Scholar Project of Shandong Province (No. ts201511004)
文摘Fossil fuel exhaustion and overdevelopment usually lead to a recession,which is worsened by the environmental pollution.So it is of high priority to develop high-efficiency energy storage device.Here,agreen and environment-friendly strategy is devised to fabricate carbon materials from biomass.By water extraction and alcohol precipitation,polysaccharide is extracted from loquat leaves.After calcining under high temperature,hierarchical porous carbon materials(HPCM)are obtained,possessing a variety of macropores,mesopores and micropores.Such ample and hierarchical pores enable the electrolyte infiltration and the buffering of the volume expansion of sulfur in repeated electrochemical reactions.The structure stability of the entire electrode can thus be well maintained.When evaluated as the scaffold for sulfur,the electrochemical performance of carbon/sulfur composite was tested.Even after 500 cycles,the reversible capacity is retained as high as 485.4 mA·h/g at the current density of 1.6 A/g.It also offers a notable rate capability,attaining the discharge capacity of 700.7 mA·h/g at 2 C.All the electrochemical performance results prove the feasibility of the proposed strategy.
基金the funding support from the National Key Research and Development Program of China(grant No.2018YFA0702001)the National Natural Science Foundation of China(grant Nos.22071225 and 22221003)+4 种基金the Plan for Anhui Major Provincial Science&Technology Project(grant Nos.202203a0520013 and 202103a05020015)the Fundamental Research Funds for the Central Universities(grant No WK2060190103)the Joint Funds from Hefei National Synchrotron Radiation Laboratory(grant No.KY2060000175)Collaborative Innovation Program of Hefei Science Center of CAS(grant No.2021HSC-CIP015)USTC Research Funds of the Double First-Class Initiative.
文摘Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and conversion.Herein,we report a general and simple zinc salts-assisted method for the synthesis of HPCs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and wastes.During the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in carbons.The prepared HPCs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size distributions.Moreover,the zinc salts can be recovered and recycled,supporting the sustainable production of HPCs on large scale.The prepared HPCs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.
基金supported by the Ningbo’s Industrial Technology Innovation and Industrialization of Scientific and Technological Achievements Program(2013B6003)
文摘Sodium fulvic acid based hierarchical porous carbons(SFA-HPCs) with a specific surface area of 1919 m^2·g^(–1) and total volume of 1.7 cm^3·g^(–1) has been synthesized by a simple self-template method. The carbon skeleton can be formatted by the decomposition process of sodium fulvic acid(SFA) in a N_2 atmosphere. The sodium compund in SFA is used as a self-template to create the hierarchical porous structure. The unique hierarchical structure of SFA-HPCs provides an efficient pathway for electrolyte ions to be diffused into the internal surfaces of bulk electrode particles. It results in a high charge storage capacitance of 186 F·g^(–1) at current load of 40 A·g^(–1). The capacitance of 230 F·g^(–1) at 0.05 A·g^(–1) and 186 F·g^(–1) at 40 A·g^(–1) show its good rate capability. Besides, it also achieves desirable cycling stability, 99.4% capacitance remained after 10000 cycles at 40 A·g^(–1).
基金supported by the National Natural Science Foundation of China(No.51903099 and 51991353)Huazhong University of Science and Technology(No.3004013134)the 100 Talents Program of the Hubei Provincial Government,and the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003).
文摘Wood-based bilayer solar evaporators,which possess cooperative advantages of natural wood and photothermal conversion coating including fast water transportation,low heat conduction,renewability,and high light absorbability,hold great promise for water purification.However,previous studies suffer from low evaporation rates and high cost of coatings,and lack a deep understanding how the porous structures of coating layer function.Herein,a novel bilayer solar evaporator is designed through facile surface coating of wood by low-cost porous carbon from controlled carbonization of polyester waste.The porous carbon bears rich oxygen-containing groups,well-controlled micro-/meso-/macropores,and high surface areas(1164 m^(2) g^(−1)).It is proved that porous carbon improves sunlight absorption and promotes the formation of numerous water clusters to reduce water evaporation enthalpy.Owing to these combined features,the bilayer solar evaporator exhibits high evaporation rate(2.38 kg m^(−2) h^(−1)),excellent longterm stability,and good salt resistance.More importantly,a large-scale solar desalination device for outdoor experiments is developed to produce freshwater from seawater.The daily freshwater production amount(3.65 kg m^(−2))per unit area meets the daily water consumption requirement of one adult.These findings will inspire new paradigms toward developing efficient solar steaming technologies for desalination to address global freshwater shortage.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea by the Korea government(MEST)(grant number NRF2019R1A2C4069922)the“LG Research Fund for New Faculty”by LG Chem。
文摘Porous carbon has been applied for lithium-sulfur battery cathodes,and carbonized metal-organic framework(MOF)is advantageous in tuning the morphology.Herein,we have systematically synthesized water-distorted MOF(WDM)derived porous carbon via controlling the proportion of both water in a mixed solvent(dimethylformamide and water)and ligand in MOF-5 precursors(metal and ligand),which is categorized by its morphology(i.e.Cracked stone(closed),Tassel(open)and Intermediate(semi-open)).For example,decrease in water and increase in ligand content induce Cracked stone WDMs which showed the highest specific surface area(2742-2990 m^(2)/g)and pore volume(2.81-3.28 cm^(3)/g)after carbonization.Morphological effect of carbonized WDMs(CWDMs)on battery performance was examined by introducing electrolytes with different sulfur reduction mechanisms(i.e.DOL/DME and ACN_(2) LiTFSITTE):Closed framework effectively confines polysulfide,whereas open framework enhances electrolyte accessibility.The initial capacities of the batteries were in the following order:Cracked stone>Intermediate>Tassel for DOL/DME and Intermediate>Tassel>Cracked stone for ACN_(2) LiTFSI-TTE.To note,Intermediate CWDM exhibited the highest initial capacity and retained capacity after 100 cycles(1398 and 747 mAh/g)in ACN_(2) LiTFSI-TTE electrolyte having advantages from both open and closed frameworks.In sum,we could correlate cathode morphology(openness and pore structure)and electrolyte type(i.e.polysulfide solubility)with lithium-sulfur battery performance.
基金This work was funded by Development and Promotion of Science Technology Talents(DPST)Research Grant(Grant No.017/2559)the Institute for the Promotion of Teaching Science and Technology(IPST),Thailand.
文摘The novel and facile preparation of magnetically interconnected micro/macroporous structure of monolithic porous carbon adsorbent(MPCA)were designed and presented herein.The synthesis was achieved via conventional freezedrying and pyrolysis processes.In this study,sodium alginate and wasted black liquor were employed as starting precursors.Sodium alginate acts as a template of materials,whereas black liquor,the wasted product from the paper industry with plentiful of lignin content and alkaline solution,played an essential role in the reinforcement and activation of porosity for the resulting materials.Moreover,both the precursors were well dissolved in Fe^(3+) solution,providing a simple addition of a magnetic source in a one-pot synthesis.The interconnected micro/macroporous structures were generated through freeze-drying and,subsequently the pyrolysis process.The obtained cylindricalshaped monolithic porous carbon adsorbent(MPCA-700)showed high mechanical stability,a high BET specific surface area(902 m^(2)/g).Such aforementioned features were considered suitable to make the synthesized monolith as an adsorbent for the removal of heavy metal ions.The maximum adsorption capacity of MPCA-700 towards Pb^(2+) ions was 76.34 mg/g at pH 5.The adsorption studies illustrated that adsorption kinetics and isotherm perfectly fitted with the pseudo-second-order kinetics model and Langmuir isotherm,respectively.This work presents a promising protocol to reduce the overall costs in the preparation of renewable adsorbents with good adsorption efficiency and regeneration.
基金financialy supported by National Natural Science Foundation of China(Grants 22005298,22125903,51872283,22075279,22279137)Dalian Innovation Support Plan for High Level Talents(2019RT09)+3 种基金Dalian National Laboratory For Clean Energy(DNL),CAS,DNL Cooperation Fund,CAS(DNL201912,DNL201915,DNL202016,DNL202019),DICP(DICP I2020032)The Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLUDNL Fund 2021002,YLU-DNL Fund 2021009)Suzhou University Scientific Research Platform(2021XJPT07)China Postdoctoral Science Foundation(2019 M661141)
文摘The Li-ion capacitors(LICs)develop rapidly due to their double-high features of high-energy density and high-power density.However,the relative low capacity of cathode and sluggish kinetics of anode seriously impede the development of LICs.Herein,the precisely pore-engineered and heteroatomtailored defective hierarchical porous carbons(DHPCs)as large-capacity cathode and high-rate anode to construct high-performance dual-carbon LICs have been developed.The DHPCs are prepared based on triple-activation mechanisms by direct pyrolysis of sustainable lignin with urea to generate the interconnected hierarchical porous structure and plentiful heteroatominduced defects.Benefiting from these advanced merits,DHPCs show the well-matched high capacity and fast kinetics of both cathode and anode,exhibiting large capacities,superior rate capability and long-term lifespan.Both experimental and computational results demonstrate the strong synergistic effect of pore and dopants for Li storage.Consequently,the assembled dual-carbon LIC exhibits high voltage of 4.5 V,high-energy density of 208 Wh kg^(−1),ultrahigh power density of 53.4 kW kg^(−1)and almost zerodecrement cycling lifetime.Impressively,the full device with high mass loading of 9.4 mg cm^(−2)on cathode still outputs high-energy density of 187 Wh kg^(−1),demonstrative of their potential as electrode materials for high-performance electrochemical devices.
基金The authors gratefully acknowledge the financial support by the Joint Funds of the Natural Science Basic Research Project of Shaanxi Province(2021JLM-23)University Joint Project of Shaanxi Province(2021GXLH-Z-067)+3 种基金Anhui Provincial Natural Science Foundation for Outstanding Young Scholar(2208085Y05)Anhui Provincial Scientific Reuter Foundation for Returned Scholars(2022LCX030)the National Natural Science Foundation of China(51801144)Guangxi Key Labo-ratory of Low Carbon Energy Material(2021GXKLLCEM04)。
文摘A robust three-dimensional(3D)interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries.Herein,cellulose-based 3D hierarchical porous carbon(HPC)and two-dimensional(2D)lamellar porous carbon(LPC)are employed as the sulfur host and polysulfide-proof inter-layer,respectively,for a Li–S battery.The 3D HPC displays a cross-linked macroporous structure,which allows high sulfur loading and restriction capability and provides unobstructed electrolyte diffusion channels.With a stackable carbon sheet of 2D LPC that has a large plane view size and is ultrathin and porous,the LPC-coated separator effectively inhibits polysulfides.An optimized combination of the HPC and LPC yields an electrode structure that effectively protects the lithium anode against corrosion by polysulfides,giving the cell a high ca-pacity of 1339.4 mAh g^(-1) and high stability,with a capacity decay rate of 0.021% per cycle at 0.2C.This work provides a new understanding of biomaterials and offers a novel strategy to improve the performance of Li–S batteries for practical applications.