Different zeolites supported Pt catalystswithmicro-mesoporous structurewere prepared by organic base tetrapropylammonium hydroxide(TPAOH)treatment and their catalytic oxidation activity for various volatile organic co...Different zeolites supported Pt catalystswithmicro-mesoporous structurewere prepared by organic base tetrapropylammonium hydroxide(TPAOH)treatment and their catalytic oxidation activity for various volatile organic compounds(VOCs)were evaluated.The results reveal that the synergistic effect between Pt nanoparticles and surface acid sites plays an important role in VOCs low-temperature removal.The small size and high dispersion of Pt nanoparticles on the surface of the zeolites would promote the catalytic oxidation of aromatics and alkanes over the Pt/zeolite catalysts,while strong acidity and abundant acid sites of catalysts are in favour of the oxidation of the VOCs containingNandOheteroatoms.In addition,it was found that Pt/ZSM-5 catalyst exhibits the highest oxidation activity for various VOCs low-temperature removal amongst all the catalysts due to the balance of both Pt dispersion and abundant acid sites in the catalyst.This comprehensive consideration should be very helpful when designing and preparing novel catalysts for the low-temperature removal of VOCs.展开更多
Herein,a porous oil-containing material with hierarchical pore structure was successfully prepared through microtexturing large pores on the surface of porous polyimide(PPI)with single-level small pores.Compared to th...Herein,a porous oil-containing material with hierarchical pore structure was successfully prepared through microtexturing large pores on the surface of porous polyimide(PPI)with single-level small pores.Compared to the conventional oil-containing material,the hierarchically porous oil-containing material exhibited high oil-content,and retained excellent mechanical properties and high oil-retention because of the synergistic effects of large pores and small pores.Furthermore,the lubricant stored in the hierarchically porous polyimide could release to the interface under thermal-and-mechano-stimuli,and the released lubricant could be reabsorbed into the hierarchically porous polyimide via the capillary-force offered by the porous channel.Based on the high oil-content and recyclable oil release/reabsorption,the hierarchically porous oil-containing polyimide exhibited excellent lubrication performance(coefficient of friction was 0.057).Furthermore,the composite could perform 1,069 cycles of smart lubrication(1 h per cycle),which significantly extended the service life of the hierarchically porous oil-containing smart lubrication material.展开更多
Carbon–silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal enviro...Carbon–silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal environment.The physicochemical properties of the materials were characterized by nitrogen physical adsorption(BET),scanning electron microscopy(SEM),and thermogravimetric(TG),and the adsorption properties of various organic waste gases were investigated.The results showed that microporous carbon materials were introduced successfully into the silica gel channels,thus showing the high adsorption capacity of activated carbon in high humidity organic waste gas,and the high stability and mechanical strength of the silica gel.The dynamic adsorption behavior confirmed that the carbon–silica material had excellent adsorption capacity for different volatile organic compounds(VOCs).Furthermore,the carbon–silica material exhibited excellent desorption characteristics:adsorbed toluene was completely desorbed at 150℃,thereby showing superior regeneration characteristics.Both features were attributed to the formation of hierarchical pores.展开更多
A Zn-containing graphite carbon(Zn-GC)with uniform Zn metal sites and hierarchical pore structure was obtained by pyrolysis of Zn-based metal organic framework(MOF).Zn-GC exhibited excellent adsorption capacity and re...A Zn-containing graphite carbon(Zn-GC)with uniform Zn metal sites and hierarchical pore structure was obtained by pyrolysis of Zn-based metal organic framework(MOF).Zn-GC exhibited excellent adsorption capacity and reproducibility for formaldehyde.The adsorption capacity of Zn-GC was 736 times that of commercial activated carbon and 5.6 times that of ZSM-5 adsorbents.The characterization and experimental results showed that the surface chemical characteristics of the adsorption material play an important role in the adsorption performance.The superior performance was attributed to Zn metal sites and oxygen-containing functional groups on the MOF derivative as well as hierarchical pore structure.The material showed a great potential in the field of organic pollutant removal.展开更多
In the work,we propose an efficient one-pot approach for synthesis of a new type of mesoporous silica nanoparticles(MSNs).That can be successfully realized by using tetraethylorthosilicate(TEOS) and N-[3-(trimethoxysi...In the work,we propose an efficient one-pot approach for synthesis of a new type of mesoporous silica nanoparticles(MSNs).That can be successfully realized by using tetraethylorthosilicate(TEOS) and N-[3-(trimethoxysilyl)propyl]ethylenediamine(TSD) as the silica precursors and cetyltrimethylammonium bromide(CTAB) as the structure-directing agent through a facile assembly process.The as-synthesized MSNs possess a spherical morphology with about 230 nm,a relatively high surface area of133 m^2/g,and a hierarchical pore size distribution.When applied as the sorbents,the amine-functioned MSNs demonstrate the enhanced adsorption capacity for CO2 capture(at 1 bar,15 vol% CO2,up to80.5 mg/g at 75℃),high selectivity,and good cycling durability,benefiting from the suitable modification of polyethyleneimine.展开更多
Hollow core-shell structure nanomaterials have been broadly used in energy storage, catalysis, reactor,and other fields due to their unique characteristics, including the synergy between different materials,a large sp...Hollow core-shell structure nanomaterials have been broadly used in energy storage, catalysis, reactor,and other fields due to their unique characteristics, including the synergy between different materials,a large specific surface area, small density, large charge carrying capacity and so on. However, their synthesis processes were mostly complicated, and few researches reported one-step encapsulation of different valence states of precious metals in carbon-based materials. Hence, a novel hollow core-shell nanostructure electrode material, RuO_(2)@Ru/HCs, with a lower mass of ruthenium to reduce costs was constructed by one-step hydrothermal method with hard template and co-assembled strategy, consisting of RuO_(2) core and ruthenium nanoparticles(Ru NPs) in carbon shell. The Ru NPs were uniformly assembled in the carbon layer, which not only improved the electronic conductivity but also provided more active centers to enhance the pseudocapacitance. The RuO_(2) core further enhanced the material’s energy storage capacity. Excellent capacitance storage(318.5 F·g^(-1)at 0.5 A·g^(-1)), rate performance(64.4%) from 0.5 A·g^(-1)to 20 A·g^(-1), and cycling stability(92.3% retention after 5000 cycles) were obtained by adjusting Ru loading to 0.92%(mass). It could be attributed to the wider pore size distribution in the micropores which increased the transfer of electrons and protons. The symmetrical supercapacitor device based on RuO_(2)@Ru/HCs could successfully light up the LED lamp. Therefore, our work verified that interfacial modification of RuO_(2) and carbon could bring attractive insights into energy density for nextgeneration supercapacitors.展开更多
A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas,...A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas, total pore volumes and microporepercentages of the CO_2-activated samples evidently increase with increasing activation temperature from 800 to950 °C, while the N contents show a contrary trend from7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample(CANHCS-950) has the largest surface area(2072 m^2 g^(-1)), pore volume(1.96 cm^3 g^(-1)), hierarchical micro-mesopore distributions(1.2, 2.6 and 6.2 nm), hollow macropore cores(*91 nm)and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions.Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction(ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4 e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications.展开更多
The application of commercial carbon fiber cloth(CFC) in energy storage equipment is limited by its low specific capacitance and energy density. By a simple one-step activation treatment, the specific surface area of ...The application of commercial carbon fiber cloth(CFC) in energy storage equipment is limited by its low specific capacitance and energy density. By a simple one-step activation treatment, the specific surface area of CFCs with porous structure can be increased considerably from 3.9 up to 875 m^2/g and the electrochemical properties of CFCs can be improved by three orders of magnitude(1324 mF/cm^2). Moreover,the hydrophobicity of CFCs can be transformed into superhydrophilicity. However, the electrochemical performance of CFCs does not show a positive correlation with specific surface area but have a strong relationship with the hierarchical pore distribution forged by the annealing treatment. Only moderate micropore and mesoporous ratio enables optimizing the electrochemical performance of CFCs.展开更多
Heteroatom-doped carbon materials have demonstrated great potential in the electrochemical reduction reaction of CO_(2)(CO_(2)RR)due to their versatile structure and function.However,rational structure control remains...Heteroatom-doped carbon materials have demonstrated great potential in the electrochemical reduction reaction of CO_(2)(CO_(2)RR)due to their versatile structure and function.However,rational structure control remains one challenge.In this work,we reported a unique carbon precursor of soft template-containing porous poly(ionic liquid)(PIL)that was directly synthesized via free-radical self-polymerization of ionic liquid monomer in a soft template route.Variation of the carbonization temperature in a direct pyrolysis process without any additive yielded a series of carbon materials with facile adjustable textural properties and N species.Significantly,the integration of soft-template in the PIL precursor led to the formation of hierarchical porous carbon material with a higher surface area and larger pore size than that from the template-free precursor.In CO_(2)RR to CO,the champion catalyst gave a Faraday efficiency of 83.0%and a current density of 1.79 mA·cm^(-2)at-0.9 V vs.reversible hydrogen electrode(vs.RHE).The abundant graphite N species and hierarchical pore structure,especially the unique hierarchical small-/ultramicropores were revealed to enable better CO_(2)RR performance.展开更多
To investigate the effect of texture structure on the desulfurization performance in the Ni/ZnO reactive adsorption desulfurization(RADS) system,two kinds of ZnO porous materials with rod-shaped morphology were synt...To investigate the effect of texture structure on the desulfurization performance in the Ni/ZnO reactive adsorption desulfurization(RADS) system,two kinds of ZnO porous materials with rod-shaped morphology were synthesized and their structure was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and N2 adsorption/desorption.The formation mechanisms of hierarchical porous ZnO(ZnO with meso and macro pores) were also studied.Their application performance was evaluated in the RADS process over Ni/ZnO absorbent.Due to the difference in structure between the two kinds of ZnO,the two ZnO based adsorbents showed different desulfurization activity.展开更多
Titanium phosphonate adsorbent materials with hierarchically porous structure were fabricated using the hydrolysis of tetrabutyl titanate in different organophosphonic acids solutions. Based on the macroporous structu...Titanium phosphonate adsorbent materials with hierarchically porous structure were fabricated using the hydrolysis of tetrabutyl titanate in different organophosphonic acids solutions. Based on the macroporous structure of 100-2000 nm in size, a worm-hole like mesostructure was in the macropore walls, which was supported by the scanning electron microscopy(SEM), transmission electron microscopy(TEM), and N2 sorption analysis. Fourier transform infrared spectroscopy(FT-IR) data indicated the organic groups inside the solid materials framework. NH3 adsorption detection was performed using titanium phosphonate adsorbent materials and some significant results were obtained. The adsorption mechanism was also discussed in this study. Large adsorption amount(75.2 mg/g) was mainly attributed to the acid site via acid-base reactions and the physical adsorption site via Van der Waals forces. Resultant materials could effectively restrain the desorption of adsorbent NH3 back into air causing secondary pollution, so it could make a promising potential use in decontamination of gas pollutants in the future.展开更多
The main challenge in the dehydration of glycerol to acrolein lies in overcoming catalystdeactivation and improving the selectivity to acrolein. The relationship between theacidity in the mesoporous channels and catal...The main challenge in the dehydration of glycerol to acrolein lies in overcoming catalystdeactivation and improving the selectivity to acrolein. The relationship between theacidity in the mesoporous channels and catalytic performance of glycerol dehydration israrely reported. In this work, to investigate the influence of acidity in the mesoporouschannels of hierarchical ZSM-5 catalysts on the dehydration of glycerol to acrolein, a seriesof hierarchical ZSM-5 zeolites with comparable mesoporous volume and mesoporous sizebut different acid properties in mesopores have been successfully prepared via alkalinetreatment. The sample with the abundant mesoporosity and highest acidity display thebest performance.展开更多
Carbon materials are effective substitutes for Pt counter electrodes(CEs) in dye-sensitized solar cells(DSSCs). However, many of these materials, such as carbon nanotubes and graphene, are expensive and require comple...Carbon materials are effective substitutes for Pt counter electrodes(CEs) in dye-sensitized solar cells(DSSCs). However, many of these materials, such as carbon nanotubes and graphene, are expensive and require complex preparation process. Herein, waste lignin, recycled from hazardous black liquors,is used to create oxygen-nitrogen-sulfur codoped carbon microspheres for use in DSSC CEs through the facile process of low-temperature preoxidation and high-temperature self-activation. The large number of ester bonds formed by preoxidation increase the degree of cross-linking of the lignin chains, leading to the formation of highly disordered carbon with ample defect sites during pyrolysis. The presence of organic O/N/S components in the waste lignin results in high O/N/S doping of the pyrolysed carbon,which increases the electrolyte ion adsorption and accelerates the electron transfer at the CE/electrolyte interface, as confirmed by density functional theory(DFT) calculations. The presence of inorganic impurities enables the construction of a hierarchical micropore-rich carbon structure through the etching effect during self-activation, which can provide abundant catalytically active sites for the reversible adsorption/desorption of electrolyte ions. Under these synergistic effects, the DSSCs that use this novel carbon CE achieve a quite high power-conversion efficiency of 9.22%. To the best of our knowledge, the value is a new record reported so far for biomass-carbon-based DSSCs.展开更多
Aqueous Zn-ion hybrid supercapacitors(ZHSs)are increasingly being studied as a novel electrochemical energy storage system with prominent electrochemical performance,high safety and low cost.Herein,high-energy and ant...Aqueous Zn-ion hybrid supercapacitors(ZHSs)are increasingly being studied as a novel electrochemical energy storage system with prominent electrochemical performance,high safety and low cost.Herein,high-energy and anti-self-discharge ZHSs are realized based on the fibrous carbon cathodes with hierarchically porous surface and O/N heteroatom functional groups.Hierarchically porous surface of the fabricated free-standing fibrous carbon cathodes not only provides abundant active sites for divalent ion storage,but also optimizes ion transport kinetics.Consequently,the cathodes show a high gravimetric capacity of 156 mAh g^(−1),superior rate capability(79 mAh g^(−1)with a very short charge/discharge time of 14 s)and exceptional cycling stability.Meanwhile,hierarchical pore structure and suitable surface functional groups of the cathodes endow ZHSs with a high energy density of 127 Wh kg−1,a high power density of 15.3 kW kg^(−1)and good anti-self-discharge performance.Mechanism investigation reveals that ZHS electrochemistry involves cation adsorption/desorption and Zn_(4)SO_(4)(OH)_(6)·5H_(2)O formation/dissolution at low voltage and anion adsorption/desorption at high voltage on carbon cathodes.The roles of these reactions in energy storage of ZHSs are elucidated.This work not only paves a way for high-performance cathode materials of ZHSs,but also provides a deeper understanding of ZHS electrochemistry.展开更多
Constructing high-performance electrodes with both wide potential window(e.g.≥2 V in aqueous electrolyte)and excellent mechanical flexibility represents a great challenge for supercapacitors.Because of the outstandin...Constructing high-performance electrodes with both wide potential window(e.g.≥2 V in aqueous electrolyte)and excellent mechanical flexibility represents a great challenge for supercapacitors.Because of the outstanding conductivity and flexibility,carb on cloth(CC)has show n unlimited prospects for constructing flexible electrodes,but is rarely used directly as electrode material due to its electrochemical inertness and small specific surface area.To tackle these two critical limitations,we design a novel redox-etching strategy to synthesize CC-based electrode with 3D interconnecting pore structure.The sponge-like highly porous CC was further activated by strong oxidant to form abundant oxygenic groups,which occupy the interior and surface of current collector to render substantial pseudocapacitance.The as-synthesized CC electrode yielded an impressive capacitance of 4035 mF cm^(-2) at 3 mA cm^(-2) and satisfying cycling durability in a wide potential range of-1-1 V vs.SCE,which surpass the majority of reported CC-based electrodes.A symmetric supercapacitor with stable voltage of 2 V is assembled and delivers remarkable energy density of 6.57 mWh cm^(-3).Significantly,the device demonstrates an unparalleled flexibility with no capacitive decay after 100 bending cycles.This facile chemical etching and post-treatment processes are designed for large-scale manufacturing of the CC electrodes by providing high surface area and abundant electrochemically active sites,promising for industry application.The innovative synthetic strategy ope ns up new opportunities for high-performance flexible en ergy storage.展开更多
Owing to the tunable compositions and versatile functionality,the development of eco-friendly metal–phenolic coordination crystals derivatives is highly anticipated for electromagnetic wave absorption.In this study,t...Owing to the tunable compositions and versatile functionality,the development of eco-friendly metal–phenolic coordination crystals derivatives is highly anticipated for electromagnetic wave absorption.In this study,three kinds of magnetic hollow carbon spheres(HCSs)with macro-meso-microporous characteristics,including Fe/HCS,Co/HCS,and CoNi/HCS,are successfully fabricated via the co-operative hard template and self-assembling process,in which magnetic particles are encapsulated in carbon shell matrix after the pyrolysis of metal–polyphenol coordination crystals and further subsequent template removal.On the one hand,hierarchical macro-meso-micropores effectively balance the impedance gap between absorbers and air and introduce structural defects or distortion,leading to matched impedance and enhanced dipolar/defect polarization.On the other hand,wrapped magnetic particles provide uncountable hetero-interfaces and induce ferromagnetic resonance,resulting in strengthened interfacial polarization and additional magnetic loss.In particular,enhanced minimum reflection loss(RL,min)and broadband effective absorption bandwidth(EAB)are achieved with only 10 wt.%filler loading.Specifically,the RL,min and EAB values are-57.5 dB and 7.2 GHz for Fe/HCS,-50.0 dB and 5.8 GHz for Co/HCS,and-52.1 dB and 6.7 GHz for CoNi/HCS,respectively.Moreover,this work provides us a modular-assembly strategy to regulate the hollow cavity of absorbers and simultaneously manipulates the chemical components of absorbers to regulate electromagnetic wave absorption performance.展开更多
Hierarchically porous materials play an important role in facilitating mass transport and improving efficiency of adsorption and separation processes. In this paper, a new strategy is proposed to realize a hierarchica...Hierarchically porous materials play an important role in facilitating mass transport and improving efficiency of adsorption and separation processes. In this paper, a new strategy is proposed to realize a hierarchically porous metal-organic framework ([Cu2(OH)(L)]'(DMF)0.8 (FJU-11, H3L=3,5-(4-carboxybenzyloxy)benzoic acid, DMF= N,N-dimethylformamide) via using semi-rigid multi-carboxylic acids. Interestingly, FJU-11 possesses the large adsorption capacities and small isosteric heats toward CO2. The column breakthrough experiment for FJU-11 highlights its potential application in the separation of the flue gas.展开更多
Aqueous rechargeable zinc-iodine batteries(ZIBs)emerging as a promising energy storage alternative have attracted considerable attention.However,ZIBs still suffer from the severe shuttle effect of polyiodide and poor ...Aqueous rechargeable zinc-iodine batteries(ZIBs)emerging as a promising energy storage alternative have attracted considerable attention.However,ZIBs still suffer from the severe shuttle effect of polyiodide and poor reversibility,leading to the poor cycling lifetime and potential safety issues.Herein,the assembly of Al-based metal-organic frameworks(Al-MOFs)in the presence of polyacrylonitrile(PAN)via electrospinning technique enables the formation of Al-MOF/PAN fibers.With the subsequent pyrolysis,the hierarchical porous carbon fibers with nitrogen doping(NPCNFs)are prepared for loading iodine.Benefiting from the confinement effect of the highly porous carbon network and the nitrogen doping,the self-supported carbon nanofiber electrode is capable of inhibiting the shuttle effect of polyiodide species.Especially,the in-situ Raman spectroscopy reveals the reversible two-step conversion reaction between iodine and polyiodide,which enables the best cycling stability for over 6,000 cycles with negligible capacity.This work demonstrates an efficient approach to regulating the porous structure and surface properties in the design of advanced iodine electrodes for high-performance ZIBs.展开更多
Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing re...Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing research interest and demonstrated promising potentials in various applications.However,regulating the nanostructure of 2 D porous carbon nanosheets by facile and efficient strategies remains a great challenge.Herein,we develop a new strategy to construct Fe,N-codoped hierarchical porous carbon nanosheets(Fe-N-HPCNS)by using 2 D Fe-Zn layered double hydroxides(Fe-Zn-LDH)as multifunctional templates.Fe-Zn-LDH could functionalize not only as 2 D structure directing agents but also as ternary hierarchical porogens for micro-,meso-and macropores and in situ Fe dopants.This multifunctional templating strategy toward 2 D porous carbon nanosheets can improve the utilization of templates and shows great advantages against conventional procedures that additional porogens and/or dopants are often needed.展开更多
基金supported by a grant from the National Key Research and Development Program of China (No. 2016YFC0204300)the Nature Science Foundation of China (No. 21477109)
文摘Different zeolites supported Pt catalystswithmicro-mesoporous structurewere prepared by organic base tetrapropylammonium hydroxide(TPAOH)treatment and their catalytic oxidation activity for various volatile organic compounds(VOCs)were evaluated.The results reveal that the synergistic effect between Pt nanoparticles and surface acid sites plays an important role in VOCs low-temperature removal.The small size and high dispersion of Pt nanoparticles on the surface of the zeolites would promote the catalytic oxidation of aromatics and alkanes over the Pt/zeolite catalysts,while strong acidity and abundant acid sites of catalysts are in favour of the oxidation of the VOCs containingNandOheteroatoms.In addition,it was found that Pt/ZSM-5 catalyst exhibits the highest oxidation activity for various VOCs low-temperature removal amongst all the catalysts due to the balance of both Pt dispersion and abundant acid sites in the catalyst.This comprehensive consideration should be very helpful when designing and preparing novel catalysts for the low-temperature removal of VOCs.
基金financially supported by the National Key R&D Program of China(2020YFB2006901)National Natural Science Foundation of China(51935006)+2 种基金CAS Project for Young Scientists in Basic Research(YSBR-023)Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2020417)Key Research Program of the Chinese Academy of Sciences(XDPB24).
文摘Herein,a porous oil-containing material with hierarchical pore structure was successfully prepared through microtexturing large pores on the surface of porous polyimide(PPI)with single-level small pores.Compared to the conventional oil-containing material,the hierarchically porous oil-containing material exhibited high oil-content,and retained excellent mechanical properties and high oil-retention because of the synergistic effects of large pores and small pores.Furthermore,the lubricant stored in the hierarchically porous polyimide could release to the interface under thermal-and-mechano-stimuli,and the released lubricant could be reabsorbed into the hierarchically porous polyimide via the capillary-force offered by the porous channel.Based on the high oil-content and recyclable oil release/reabsorption,the hierarchically porous oil-containing polyimide exhibited excellent lubrication performance(coefficient of friction was 0.057).Furthermore,the composite could perform 1,069 cycles of smart lubrication(1 h per cycle),which significantly extended the service life of the hierarchically porous oil-containing smart lubrication material.
基金supported by the Natural Science Foundation of China(Nos.21506194 and 21676255)Zhejiang Provincial Natural Science Foundation of China(Nos.Y14E080008and Y16B070025)
文摘Carbon–silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal environment.The physicochemical properties of the materials were characterized by nitrogen physical adsorption(BET),scanning electron microscopy(SEM),and thermogravimetric(TG),and the adsorption properties of various organic waste gases were investigated.The results showed that microporous carbon materials were introduced successfully into the silica gel channels,thus showing the high adsorption capacity of activated carbon in high humidity organic waste gas,and the high stability and mechanical strength of the silica gel.The dynamic adsorption behavior confirmed that the carbon–silica material had excellent adsorption capacity for different volatile organic compounds(VOCs).Furthermore,the carbon–silica material exhibited excellent desorption characteristics:adsorbed toluene was completely desorbed at 150℃,thereby showing superior regeneration characteristics.Both features were attributed to the formation of hierarchical pores.
基金This work was supported by The National Key Research and Development Program of China(No.2018YFB0605200)Scientific Research Project of Guangzhou City(No.201804020026)+1 种基金National Natural Science Foundation of China(No.21777047)National Training Program of Innovation and Entrepreneurship for Undergraduates(No.S201910561224).
文摘A Zn-containing graphite carbon(Zn-GC)with uniform Zn metal sites and hierarchical pore structure was obtained by pyrolysis of Zn-based metal organic framework(MOF).Zn-GC exhibited excellent adsorption capacity and reproducibility for formaldehyde.The adsorption capacity of Zn-GC was 736 times that of commercial activated carbon and 5.6 times that of ZSM-5 adsorbents.The characterization and experimental results showed that the surface chemical characteristics of the adsorption material play an important role in the adsorption performance.The superior performance was attributed to Zn metal sites and oxygen-containing functional groups on the MOF derivative as well as hierarchical pore structure.The material showed a great potential in the field of organic pollutant removal.
基金support from the Shanghai Pujiang Program (No.17PJD015)Shuguang Program supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission (No.18SG035)
文摘In the work,we propose an efficient one-pot approach for synthesis of a new type of mesoporous silica nanoparticles(MSNs).That can be successfully realized by using tetraethylorthosilicate(TEOS) and N-[3-(trimethoxysilyl)propyl]ethylenediamine(TSD) as the silica precursors and cetyltrimethylammonium bromide(CTAB) as the structure-directing agent through a facile assembly process.The as-synthesized MSNs possess a spherical morphology with about 230 nm,a relatively high surface area of133 m^2/g,and a hierarchical pore size distribution.When applied as the sorbents,the amine-functioned MSNs demonstrate the enhanced adsorption capacity for CO2 capture(at 1 bar,15 vol% CO2,up to80.5 mg/g at 75℃),high selectivity,and good cycling durability,benefiting from the suitable modification of polyethyleneimine.
基金supported by Jinan Mingzhu Co., Ltd (HX20200364)。
文摘Hollow core-shell structure nanomaterials have been broadly used in energy storage, catalysis, reactor,and other fields due to their unique characteristics, including the synergy between different materials,a large specific surface area, small density, large charge carrying capacity and so on. However, their synthesis processes were mostly complicated, and few researches reported one-step encapsulation of different valence states of precious metals in carbon-based materials. Hence, a novel hollow core-shell nanostructure electrode material, RuO_(2)@Ru/HCs, with a lower mass of ruthenium to reduce costs was constructed by one-step hydrothermal method with hard template and co-assembled strategy, consisting of RuO_(2) core and ruthenium nanoparticles(Ru NPs) in carbon shell. The Ru NPs were uniformly assembled in the carbon layer, which not only improved the electronic conductivity but also provided more active centers to enhance the pseudocapacitance. The RuO_(2) core further enhanced the material’s energy storage capacity. Excellent capacitance storage(318.5 F·g^(-1)at 0.5 A·g^(-1)), rate performance(64.4%) from 0.5 A·g^(-1)to 20 A·g^(-1), and cycling stability(92.3% retention after 5000 cycles) were obtained by adjusting Ru loading to 0.92%(mass). It could be attributed to the wider pore size distribution in the micropores which increased the transfer of electrons and protons. The symmetrical supercapacitor device based on RuO_(2)@Ru/HCs could successfully light up the LED lamp. Therefore, our work verified that interfacial modification of RuO_(2) and carbon could bring attractive insights into energy density for nextgeneration supercapacitors.
基金the financial support from the National Key Research and Development Program of China(2016YFB0700204)NSFC(51502327,51602332)+1 种基金Science and Technology Commission of Shanghai Municipality(15520720400,15YF1413800,14DZ2261203 and 16DZ2260603)Key Project for Young Researcher of State Key Laboratory of High Performance Ceramics and Superfine Microstructure and One Hundred Talent Plan of Chinese Academy of Sciences
文摘A series of triple hierarchical micro-mesomacroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO_2 at high temperatures.The surface areas, total pore volumes and microporepercentages of the CO_2-activated samples evidently increase with increasing activation temperature from 800 to950 °C, while the N contents show a contrary trend from7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample(CANHCS-950) has the largest surface area(2072 m^2 g^(-1)), pore volume(1.96 cm^3 g^(-1)), hierarchical micro-mesopore distributions(1.2, 2.6 and 6.2 nm), hollow macropore cores(*91 nm)and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions.Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction(ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4 e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications.
基金supported by the National Natural Science Foundation of China (51932003, 51872115, and 51802110)2020 International Cooperation Project of the Department of Science and Technology of Jilin Porvince+5 种基金Program for the Development of Science & Technology of Jilin Province (Item No.20190201309JC)the Jilin Province/Jilin University co-Construction Project-Funds for New Materials (SXGJSF2017-3, Branch-2/440050316A36)the Open Project Program of Wuhan National Laboratory for Optoelectronics (2018WNLOKF022)the Program for JLU Science & Technology Innovative Research Team (JLUSTIRT, 2017TD-09)the Fundamental Research Funds for the Central Universities JLU“Double-First Class” Discipline for Materials Science & Engineering。
文摘The application of commercial carbon fiber cloth(CFC) in energy storage equipment is limited by its low specific capacitance and energy density. By a simple one-step activation treatment, the specific surface area of CFCs with porous structure can be increased considerably from 3.9 up to 875 m^2/g and the electrochemical properties of CFCs can be improved by three orders of magnitude(1324 mF/cm^2). Moreover,the hydrophobicity of CFCs can be transformed into superhydrophilicity. However, the electrochemical performance of CFCs does not show a positive correlation with specific surface area but have a strong relationship with the hierarchical pore distribution forged by the annealing treatment. Only moderate micropore and mesoporous ratio enables optimizing the electrochemical performance of CFCs.
基金support from the National Natural Science Foundation of China(Nos.22072065,U1662107,and 21476109)Six talent peaks project in Jiangsu Province(JNHB035)+3 种基金State Key Laboratory of Materials-Oriented Chemical Engineering(KL17-04)Jiangsu Provincial Science Foundation for Youths(SBK2020044703)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)High-Performance Computing Center of Nanjing Tech University。
文摘Heteroatom-doped carbon materials have demonstrated great potential in the electrochemical reduction reaction of CO_(2)(CO_(2)RR)due to their versatile structure and function.However,rational structure control remains one challenge.In this work,we reported a unique carbon precursor of soft template-containing porous poly(ionic liquid)(PIL)that was directly synthesized via free-radical self-polymerization of ionic liquid monomer in a soft template route.Variation of the carbonization temperature in a direct pyrolysis process without any additive yielded a series of carbon materials with facile adjustable textural properties and N species.Significantly,the integration of soft-template in the PIL precursor led to the formation of hierarchical porous carbon material with a higher surface area and larger pore size than that from the template-free precursor.In CO_(2)RR to CO,the champion catalyst gave a Faraday efficiency of 83.0%and a current density of 1.79 mA·cm^(-2)at-0.9 V vs.reversible hydrogen electrode(vs.RHE).The abundant graphite N species and hierarchical pore structure,especially the unique hierarchical small-/ultramicropores were revealed to enable better CO_(2)RR performance.
基金Financial support from the National Basic Research Program of China (No. 2010CB226905)the National Natural Science Foundation of China (Nos. 21176258, U1162203)the Specialized Research Fund for the Doctoral Program of Higher Education (20110133110002)
文摘To investigate the effect of texture structure on the desulfurization performance in the Ni/ZnO reactive adsorption desulfurization(RADS) system,two kinds of ZnO porous materials with rod-shaped morphology were synthesized and their structure was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and N2 adsorption/desorption.The formation mechanisms of hierarchical porous ZnO(ZnO with meso and macro pores) were also studied.Their application performance was evaluated in the RADS process over Ni/ZnO absorbent.Due to the difference in structure between the two kinds of ZnO,the two ZnO based adsorbents showed different desulfurization activity.
基金Funded by the National Science&Technology Pillar Program during the Twelfth Five-year Plan Period(2011BAK03B07)the Specialized Research Fund for the Technology Research Program of Ministry of Public Security(2014JSYJA024)the Specialized Research Fund for the Applications Innovation Program of Ministry of Public Security(2011YYCXWJXY131)
文摘Titanium phosphonate adsorbent materials with hierarchically porous structure were fabricated using the hydrolysis of tetrabutyl titanate in different organophosphonic acids solutions. Based on the macroporous structure of 100-2000 nm in size, a worm-hole like mesostructure was in the macropore walls, which was supported by the scanning electron microscopy(SEM), transmission electron microscopy(TEM), and N2 sorption analysis. Fourier transform infrared spectroscopy(FT-IR) data indicated the organic groups inside the solid materials framework. NH3 adsorption detection was performed using titanium phosphonate adsorbent materials and some significant results were obtained. The adsorption mechanism was also discussed in this study. Large adsorption amount(75.2 mg/g) was mainly attributed to the acid site via acid-base reactions and the physical adsorption site via Van der Waals forces. Resultant materials could effectively restrain the desorption of adsorbent NH3 back into air causing secondary pollution, so it could make a promising potential use in decontamination of gas pollutants in the future.
基金The work was supported by the Australian Research Council Discovery Projects(grant no.DP150103842,DP180104010,DE190101618)the SOAR Fellowship,and the Sydney Nano Grand Challenge from the University of Sydney。
文摘The main challenge in the dehydration of glycerol to acrolein lies in overcoming catalystdeactivation and improving the selectivity to acrolein. The relationship between theacidity in the mesoporous channels and catalytic performance of glycerol dehydration israrely reported. In this work, to investigate the influence of acidity in the mesoporouschannels of hierarchical ZSM-5 catalysts on the dehydration of glycerol to acrolein, a seriesof hierarchical ZSM-5 zeolites with comparable mesoporous volume and mesoporous sizebut different acid properties in mesopores have been successfully prepared via alkalinetreatment. The sample with the abundant mesoporosity and highest acidity display thebest performance.
基金supported by the National Natural Science Foundation of China (31890771 and 31901249)the Young Elite Scientists Sponsorship Program by CAST (2019QNRC001)+3 种基金the Hunan Provincial Technical Innovation Platform and Talent Program in Science and Technology (2020RC3041)the Training Program for Excellent Young Innovators of Changsha (kq2106056)the Hunan Provincial Natural Science Foundation of China (2022JJ30079)the Postgraduate Technology Innovation Project of Central South University of Forestry and Technology (2022CX02017)。
文摘Carbon materials are effective substitutes for Pt counter electrodes(CEs) in dye-sensitized solar cells(DSSCs). However, many of these materials, such as carbon nanotubes and graphene, are expensive and require complex preparation process. Herein, waste lignin, recycled from hazardous black liquors,is used to create oxygen-nitrogen-sulfur codoped carbon microspheres for use in DSSC CEs through the facile process of low-temperature preoxidation and high-temperature self-activation. The large number of ester bonds formed by preoxidation increase the degree of cross-linking of the lignin chains, leading to the formation of highly disordered carbon with ample defect sites during pyrolysis. The presence of organic O/N/S components in the waste lignin results in high O/N/S doping of the pyrolysed carbon,which increases the electrolyte ion adsorption and accelerates the electron transfer at the CE/electrolyte interface, as confirmed by density functional theory(DFT) calculations. The presence of inorganic impurities enables the construction of a hierarchical micropore-rich carbon structure through the etching effect during self-activation, which can provide abundant catalytically active sites for the reversible adsorption/desorption of electrolyte ions. Under these synergistic effects, the DSSCs that use this novel carbon CE achieve a quite high power-conversion efficiency of 9.22%. To the best of our knowledge, the value is a new record reported so far for biomass-carbon-based DSSCs.
基金National Natural Science Foundation of China(No.52002149)Shenzhen Technical Plan Projects(Nos.JC201105201100A and JCYJ20160301154114273)for financial support.
文摘Aqueous Zn-ion hybrid supercapacitors(ZHSs)are increasingly being studied as a novel electrochemical energy storage system with prominent electrochemical performance,high safety and low cost.Herein,high-energy and anti-self-discharge ZHSs are realized based on the fibrous carbon cathodes with hierarchically porous surface and O/N heteroatom functional groups.Hierarchically porous surface of the fabricated free-standing fibrous carbon cathodes not only provides abundant active sites for divalent ion storage,but also optimizes ion transport kinetics.Consequently,the cathodes show a high gravimetric capacity of 156 mAh g^(−1),superior rate capability(79 mAh g^(−1)with a very short charge/discharge time of 14 s)and exceptional cycling stability.Meanwhile,hierarchical pore structure and suitable surface functional groups of the cathodes endow ZHSs with a high energy density of 127 Wh kg−1,a high power density of 15.3 kW kg^(−1)and good anti-self-discharge performance.Mechanism investigation reveals that ZHS electrochemistry involves cation adsorption/desorption and Zn_(4)SO_(4)(OH)_(6)·5H_(2)O formation/dissolution at low voltage and anion adsorption/desorption at high voltage on carbon cathodes.The roles of these reactions in energy storage of ZHSs are elucidated.This work not only paves a way for high-performance cathode materials of ZHSs,but also provides a deeper understanding of ZHS electrochemistry.
基金financially supported by the National Natural Science Foundation of China (No. 52071171)the Liaoning Revitalization Talents Program-Pan Deng Scholars (XLYC1802005)+5 种基金the Liaoning BaiQianWan Talents Program (LNBQW2018B0048)the Natural Science Fund of Liaoning Province for Excellent Young Scholars (2019-YQ-04)the Key Project of Scientific Research of the Education Department of Liaoning Province (LZD201902)the General Project of Scientific Research of the Education Department of Liaoning Province (LJC201905)the Research Fund for the Doctoral Program of Liaoning Province (2019-BS-112)the Foundation for Young Scholars of Liaoning University (LDQN2019006).
文摘Constructing high-performance electrodes with both wide potential window(e.g.≥2 V in aqueous electrolyte)and excellent mechanical flexibility represents a great challenge for supercapacitors.Because of the outstanding conductivity and flexibility,carb on cloth(CC)has show n unlimited prospects for constructing flexible electrodes,but is rarely used directly as electrode material due to its electrochemical inertness and small specific surface area.To tackle these two critical limitations,we design a novel redox-etching strategy to synthesize CC-based electrode with 3D interconnecting pore structure.The sponge-like highly porous CC was further activated by strong oxidant to form abundant oxygenic groups,which occupy the interior and surface of current collector to render substantial pseudocapacitance.The as-synthesized CC electrode yielded an impressive capacitance of 4035 mF cm^(-2) at 3 mA cm^(-2) and satisfying cycling durability in a wide potential range of-1-1 V vs.SCE,which surpass the majority of reported CC-based electrodes.A symmetric supercapacitor with stable voltage of 2 V is assembled and delivers remarkable energy density of 6.57 mWh cm^(-3).Significantly,the device demonstrates an unparalleled flexibility with no capacitive decay after 100 bending cycles.This facile chemical etching and post-treatment processes are designed for large-scale manufacturing of the CC electrodes by providing high surface area and abundant electrochemically active sites,promising for industry application.The innovative synthetic strategy ope ns up new opportunities for high-performance flexible en ergy storage.
基金supports from the Natural Science Foundation of Shaanxi Province(No.2022JM-260)the Fundamental Research Funds for the Central Universities(No.G2022KY05109).
文摘Owing to the tunable compositions and versatile functionality,the development of eco-friendly metal–phenolic coordination crystals derivatives is highly anticipated for electromagnetic wave absorption.In this study,three kinds of magnetic hollow carbon spheres(HCSs)with macro-meso-microporous characteristics,including Fe/HCS,Co/HCS,and CoNi/HCS,are successfully fabricated via the co-operative hard template and self-assembling process,in which magnetic particles are encapsulated in carbon shell matrix after the pyrolysis of metal–polyphenol coordination crystals and further subsequent template removal.On the one hand,hierarchical macro-meso-micropores effectively balance the impedance gap between absorbers and air and introduce structural defects or distortion,leading to matched impedance and enhanced dipolar/defect polarization.On the other hand,wrapped magnetic particles provide uncountable hetero-interfaces and induce ferromagnetic resonance,resulting in strengthened interfacial polarization and additional magnetic loss.In particular,enhanced minimum reflection loss(RL,min)and broadband effective absorption bandwidth(EAB)are achieved with only 10 wt.%filler loading.Specifically,the RL,min and EAB values are-57.5 dB and 7.2 GHz for Fe/HCS,-50.0 dB and 5.8 GHz for Co/HCS,and-52.1 dB and 6.7 GHz for CoNi/HCS,respectively.Moreover,this work provides us a modular-assembly strategy to regulate the hollow cavity of absorbers and simultaneously manipulates the chemical components of absorbers to regulate electromagnetic wave absorption performance.
基金financially supported by the National Natural Science Foundation of China(52371248)National Key R&D Program of China(2021YFB3802200)+5 种基金Guangdong Basic and Applied Basic Research Foundation(2023A1515010905)he Scientific and Technological Innovation Foundation of Shunde Graduate School,USTB(BK22BE012)the funding supports from Singapore Ministry of Education(AcRF Tier 1 RS13/20 and RG4/21)A*STAR Singapore(AME YIRG A2084c0158)the Center of Hydrogen Innovation,National University of Singapore(CHI-P2022-05)Nanyang Technological University Startup Grants。
基金This work was financially supported by the National Natural Science Foundation of China (21207018, 21273033, 21573042 and 21203024) and the Fujian Science and Technology Department (2014J06003 and 2014H6007). S. X. gratefully acknowledges the support of the Recruitment Program of Global Young Experts, Program for New Century Excellent Talents in University (NCET- 10-0108), and the Award 'MinJiang Scholar Program' in Fujian Province.sity (NCET- 10-0108), and the Award 'MinJiang Scholar Program' in Fujian Province.
文摘Hierarchically porous materials play an important role in facilitating mass transport and improving efficiency of adsorption and separation processes. In this paper, a new strategy is proposed to realize a hierarchically porous metal-organic framework ([Cu2(OH)(L)]'(DMF)0.8 (FJU-11, H3L=3,5-(4-carboxybenzyloxy)benzoic acid, DMF= N,N-dimethylformamide) via using semi-rigid multi-carboxylic acids. Interestingly, FJU-11 possesses the large adsorption capacities and small isosteric heats toward CO2. The column breakthrough experiment for FJU-11 highlights its potential application in the separation of the flue gas.
基金financially supported by the National Natural Science Foundation of China(22175108)the Taishan Scholars Program of Shandong Province(tsqn20161004)+1 种基金Program for Scientific Research Innovation Team of Young Scholar in Colleges and Universities of Shandong Province(2019KJC025)the Youth 1000 Talent Program of China。
文摘Aqueous rechargeable zinc-iodine batteries(ZIBs)emerging as a promising energy storage alternative have attracted considerable attention.However,ZIBs still suffer from the severe shuttle effect of polyiodide and poor reversibility,leading to the poor cycling lifetime and potential safety issues.Herein,the assembly of Al-based metal-organic frameworks(Al-MOFs)in the presence of polyacrylonitrile(PAN)via electrospinning technique enables the formation of Al-MOF/PAN fibers.With the subsequent pyrolysis,the hierarchical porous carbon fibers with nitrogen doping(NPCNFs)are prepared for loading iodine.Benefiting from the confinement effect of the highly porous carbon network and the nitrogen doping,the self-supported carbon nanofiber electrode is capable of inhibiting the shuttle effect of polyiodide species.Especially,the in-situ Raman spectroscopy reveals the reversible two-step conversion reaction between iodine and polyiodide,which enables the best cycling stability for over 6,000 cycles with negligible capacity.This work demonstrates an efficient approach to regulating the porous structure and surface properties in the design of advanced iodine electrodes for high-performance ZIBs.
基金financially supported by the National Natural Science Foundation of China(Nos.51925308 and 51872336)the Leading Scientific,Technical and Innovation Talents of Guangdong Special Support Program(No.2017TX04C248)+3 种基金the Pearl River Talent Plan of Guangdong(No.2017GC010612)Natural Science Foundation of Guangdong(No.2021A1515011617)the Fundamental Research Funds for the Central Universities(No.20lgzd18)the Science and Technology Program of Guangzhou(Nos.202102021111 and 202002020041)。
文摘Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing research interest and demonstrated promising potentials in various applications.However,regulating the nanostructure of 2 D porous carbon nanosheets by facile and efficient strategies remains a great challenge.Herein,we develop a new strategy to construct Fe,N-codoped hierarchical porous carbon nanosheets(Fe-N-HPCNS)by using 2 D Fe-Zn layered double hydroxides(Fe-Zn-LDH)as multifunctional templates.Fe-Zn-LDH could functionalize not only as 2 D structure directing agents but also as ternary hierarchical porogens for micro-,meso-and macropores and in situ Fe dopants.This multifunctional templating strategy toward 2 D porous carbon nanosheets can improve the utilization of templates and shows great advantages against conventional procedures that additional porogens and/or dopants are often needed.