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Free radicals trigger the closure of open pores in lignin-derived hard carbons toward improved sodium-storage capacity 被引量:1
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作者 Wen-Jun Ji Zong-Lin Yi +8 位作者 Ming-Xin Song Xiao-Qian Guo Yi-Lin Wang Yi-Xuan Mao Fang-Yuan Su Jing-Peng Chen Xian-Xian Wei Li-Jing Xie Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期551-559,共9页
The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming ag... The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming agents is not well understood.Herein,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high temperatures.Excessively high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high tempera-tures.By activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard carbons.As a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors. 展开更多
关键词 Hard carbon Chemical activation Free radical SELF-HEALING Closed pores Sodium ion batteries
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The relationship between the high-frequency performance of supercapacitors and the type of doped nitrogen in the carbon electrode
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作者 FAN Ya-feng YI Zong-lin +6 位作者 ZHOU Yi XIE Li-jing SUN Guo-hua WANG Zhen-bing Huang Xian-hong SU Fang-yuan CHEN Cheng-meng 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期1015-1026,共12页
Nitrogen doping has been widely used to improve the performance of carbon electrodes in supercapacitors,particularly in terms of their high-frequency response.However,the charge storage and electrolyte ion response me... Nitrogen doping has been widely used to improve the performance of carbon electrodes in supercapacitors,particularly in terms of their high-frequency response.However,the charge storage and electrolyte ion response mechanisms of different nitrogen dopants at high frequencies are still unclear.In this study,melamine foam carbons with different configurations of surfacedoped N were formed by gradient carbonization,and the effects of the configurations on the high-frequency response behavior of the supercapacitors were analyzed.Using a combination of experiments and first-principle calculations,we found that pyrrolic N,characterized by a higher adsorption energy,increases the charge storage capacity of the electrode at high frequencies.On the other hand,graphitic N,with a lower adsorption energy,increases the speed of ion response.We propose the use of adsorption energy as a practical descriptor for electrode/electrolyte design in high-frequency applications,offering a more universal approach for improving the performance of N-doped carbon materials in supercapacitors. 展开更多
关键词 High-frequency supercapacitors Carbon electrodes Doped nitrogen species Adsorption energy DESCRIPTOR
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Optimizing band structure of CoP nanoparticles via rich-defect carbon shell toward bifunctional electrocatalysts for overall water splitting 被引量:7
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作者 Juncheng Wu Zhe‐Fan Wang +7 位作者 Taotao Guan Guoli Zhang Juan Zhang Jie Han Shengqin Guan Ning Wang Jianlong Wang Kaixi Li 《Carbon Energy》 SCIE CSCD 2023年第3期112-125,共14页
Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of... Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of TMPs.Herein,a novel method for synthesizing CoP nanoparticles encapsu-lated in a rich-defect carbon shell(CoP/DCS)is developed through the self-assembly of modified polycyclic aromatic molecules.The graft and removal of high-activity C-N bonds of aromatic molecules render the controllable design of crystallite defects of carbon shell.The density functional theory calculation indicates that the carbon defects with unpaired electrons could effectively tailor the band structure of CoP.Benefiting from the improved activity and corrosion resistance,the CoP/DCS delivers outstanding difunctional hydrogen evolution reaction(88 mV)and oxygen evolution reaction(251 mV)performances at 10 mA cm^(−2)current density.Furthermore,the coupled water electrolyzer with CoP/DCS as both the cathode and anode presents ultralow cell voltages of 1.49 V to achieve 10 mA cm^(−2)with long-time stability.This strategy to improve TMPs electrocatalyst with rich-DCS and heterogeneous structure will inspire the design of other transition metal compound electrocatalysts for water splitting. 展开更多
关键词 band structure bifunctional electrocatalysts CoP nanoparticles overall water splitting rich‐defect carbon
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Effect of N-doping-derived solvent adsorption on electrochemical double layer structure and performance of porous carbon
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作者 Zhe-Fan Wang Cheng Tang +6 位作者 Qian Sun Ya-Lu Han Zhi-Jian Wang Lijing Xie Shou-Chun Zhang Fang-Yuan Su Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期120-127,I0004,共9页
N-doped porous carbon has been extensively investigated for broad electrochemical applications.The performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to... N-doped porous carbon has been extensively investigated for broad electrochemical applications.The performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to characterize.Limited understanding of doping-derived EDL structure hinders insight into the structure-performance relations and the rational design of high-performance materials.Thus,we analyzed the mass and chemical composition variation of EDL within electrochemical operation by electrochemical quartz crystal microbalance,in-situ X-ray photoelectron spectroscopy,and time-offlight secondary ion mass spectrometry.We found that N-doping triggers specifically adsorbed propylene carbonate solvent in the inner Helmholtz plane(IHP),which prevents ion rearrangement and enhances the migration of cations.However,this specific adsorption accelerated solvent decomposition,rendering rapid performance degradation in practical devices.This work reveals that the surface chemistry of electrodes can cause specific adsorption of solvents and change the EDL structure,which complements the classical EDL theory and provide guidance for practical applications. 展开更多
关键词 Carbon materials Electrochemical double layer Electrochemical quartz crystal microbalance In-situ X-ray photoelectron spectroscopy N-DOPING
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Bimetallic AgNi nanoparticles anchored onto MOF-derived nitrogen-doped carbon nanostrips for efficient hydrogen evolution
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作者 Dandan Chen Cheng Han +6 位作者 Qiuhong Sun Junyang Ding Qi Huang Ting-Ting Li Yue Hu Jinjie Qian Shaoming Huang 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期258-266,共9页
Hydrogen energy has long been recognized as a clean alternative to conventional fossil fuels,which can be applied in a wide range of transportation and power generation applications.The rational design and engineering... Hydrogen energy has long been recognized as a clean alternative to conventional fossil fuels,which can be applied in a wide range of transportation and power generation applications.The rational design and engineering of high-performance and robust catalysts for hydrogen evolution reaction(HER)shows not a great significance but a challenge for efficient electrochemical water splitting.Herein,a new type of Nibased Ni-ABDC precursor has been obtained,which leads to the formation of N-doped porous carbon nanomaterials uniformly coated with wellproportioned bimetallic AgNi alloys via a stepwise strategy.To their credit,all samples of AgNi/NC-X are structurally calcined from the pristine AgNi-ABDC-X by tuning the different concentration of AgNO3,which means all of them maintain the vermicelli-like morphology compared with Ni-ABDC.The series of AgNi/NC-X materials can be regarded as effective electrocatalysts for HER both in acidic and alkaline media,but an acid-leaching phenomenon is observed.Among them,the as-prepared AgNi/NC-2 exhibits a low overpotential of 103 mV at the current density of 10 mA cm^(-2)and decent durability with a high retention rate of 90.9%after 10 h in 1.0 mol L^(-1)KOH electrolyte.The compelling HER properties of AgNi/NC-2 can be attributed to the synergistic effect between the hierarchical carbon materials,partial N-doping and abundant AgNi alloys.Meanwhile,this study provides a practicable method for the development of efficient HER electrocatalysts for energy applications,which can be conveniently prepared through the reasonable introduction of active components in the crystalline inorganic-organic precursors.©2021 Institute of Process Engineering,Chinese Academy of Sciences.Publishing services by Elsevier B.V.on behalf of KeAi Communications Co.,Ltd.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Metal-organic framework Carbon nanomaterial AgNi alloy Hydrogen evolution ELECTROCATALYSIS
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Ordered Macroporous MoS_(2)-Carbon Composite with Fast and Robust Sodium Storage Properties to Solve the Issue of Kinetics Mismatch of Sodium-Ion Capacitors
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作者 Weiqing Yu Chunyan Zhu +6 位作者 Rutao Wang Jianchao Chen Qingyuan Liu Shuxian Zhang Shoubao Zhang Jinfeng Sun Longwei Yin 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期202-211,共10页
Metal-ion capacitors(including Li^(+),Na^(+),and K^(+))effectively combine a battery negative electrode capable of reversibly intercalating metal cations,together with an electrical double-layer positive electrode.How... Metal-ion capacitors(including Li^(+),Na^(+),and K^(+))effectively combine a battery negative electrode capable of reversibly intercalating metal cations,together with an electrical double-layer positive electrode.However,such novel cell design has a birth defect,namely kinetics mismatch between sluggish negative electrode and fast positive electrode,thus limiting the energy-power performance.Herein,we design a MoS_(2)-carbon composite anode with the ordered macroporous architecture and interlayer-expanded feature,exhibiting the fast and reversible Na^(+)redox processes.This kinetically favored anode is coupled with a homemade activated carbon cathode that allows for the excellent electrochemical performance of sodiumion capacitor with respect to large specific capacity,high-rate capability,and robust cycling.Through quantification of the potential swings of anode and cathode via a three-electrode Swagelok cell,we for the first time observe the abnormal variation law of potential swings and thus directly providing the evidence that the kinetics gap has been filled up by this kinetically favored anode.Our results represent a crucial step toward understanding the key issues of kinetics mismatch for hybrid cell,thus propelling the development of design of kinetically favored anode materials for high-performance metalion capacitors. 展开更多
关键词 anode energy-storage devices KINETICS Molybdenum disulfide sodium-ion capacitor
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Polyetherketoneketone/carbon fiber composites with an amorphous interface prepared by solution impregnation
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作者 ZHANG Feng LI Bo-lan +5 位作者 JIAO Meng-xiao LI Yan-bo WANG Xin YANG Yu YANG Yu-qiu ZHANG Xiao-hua 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第4期692-702,共11页
Interfacial adhesion between carbon fibers(CF)and polyetherketoneketone(PEKK)is a key factor that affects the mechanical performances of their composites.It is therefore of great importance to impregnate the CF bundle... Interfacial adhesion between carbon fibers(CF)and polyetherketoneketone(PEKK)is a key factor that affects the mechanical performances of their composites.It is therefore of great importance to impregnate the CF bundles with PEKK as effi-ciently as possible.We report that PEKK with a good dispersion in a mixed solution of 4-chlorophenol and 1,2-dichloroethane can be introduced onto CF surfaces by solution impregnation and curing at 280,320,340 and 360℃.The excellent wettability or infiltra-tion of the PEKK solution guarantees a full covering and its tight binding to CFs,making it possible to evaluate the interfacial shear strength(IFSS)with the microdroplet method.The interior of the CF bundles is completely and uniformly filled with PEKK by solu-tion impregnation,leading to a high interlaminar shear strength(ILSS).The maximum IFSS and ILSS reached 107.8 and 99.3 MPa,respectively.Such superior shear properties are ascribed to the formation of amorphous PEKK in the small spaces between CFs. 展开更多
关键词 Polyetherketoneketone Carbon fiber WETTABILITY Amorphous adhesion Interfacial strength
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Cardo poly (ether sulfone) toughened E51/DETDA epoxy resin and its carbon fiber composites
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作者 WU Rong-peng ZHANG Xing-hua +3 位作者 WEI Xing-hai JING De-qi SU Wei-guo ZHANG Shou-chun 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第4期681-691,共11页
A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfo... A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase separation.After adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,respectively.These improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of CFCs.The G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control laminate.The increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region. 展开更多
关键词 Epoxy resin CFRP PES-C TOUGHNESS
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Furfural residues derived nitrogen-sulfur co-doped sheet-like carbon: An excellent electrode for dual carbon lithium-ion capacitors
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作者 Xiaoying Guo Yan Qiao +4 位作者 Zonglin Yi Christian Marcus Pedersen Yingxiong Wang Xiaodong Tian Peide Han 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1427-1439,共13页
The state-of-the-art lithium-ion capacitors (LICs),consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with tradit... The state-of-the-art lithium-ion capacitors (LICs),consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries,respectively.However,the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode degradation.Tremendous efforts have been devoted to solving the abovementioned issue.One promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode,assembling dual-carbon LIC.In this contribution,one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon,while activated carbon was obtained involving activation.Ammonium persulfate was used as expanding and doping agent simultaneously.While furfural residues (FR) were served as carbon precursor.The resulting hard carbon (FRNS-HC) and activated carbon (FRNS-AC)show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery (LIB).To be specific,374.2 m Ah g^(-1)and 123.1 m Ah g^(-1)can be achieved at 0.1 A g^(-1)and 5 A g^(-1)when FRNS-HC was tested as anode.When combined with a highly porous carbon cathode (S_(BET)=2961 m^(2)g^(-1)) synthesized from the same precursor,the LIC showed high specific energy of147.67 Wh kg^(-1)at approximately 199.93 W kg^(-1),and outstanding cycling life with negligible capacitance fading over 1000 cycles.This study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications. 展开更多
关键词 Furfural residue Ammonium persulfate Sheet-like carbon Lithium-ion capacitors Hard carbon
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Structure evolution of oxygen removal from porous carbon for optimizing supercapacitor performance 被引量:16
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作者 Siting Yuan Xianhong Huang +5 位作者 Hao Wang Lijing Xie Jiayao Cheng Qingqiang Kong Guohua Sun Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期396-404,共9页
The presence of oxygen functional groups is detrimental to the capacitive performance of porous carbon electrode in organic electrolyte. In this regards, hydrogen thermal reduction has been demonstrated effective appr... The presence of oxygen functional groups is detrimental to the capacitive performance of porous carbon electrode in organic electrolyte. In this regards, hydrogen thermal reduction has been demonstrated effective approach in removing the unstable surface oxygen while maintaining the high porosity of carbon matrix. However, the exact evolution mechanism of various oxygen species during this process, as well as the correlation with electrochemical properties, is still under development. Herein, biomass-based porous carbon is adopted as the model material to trace its structure evolution of oxygen removal under hydrogen thermal reduction process with the temperature range of 400–800 °C. The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700°C. XPS, TPRMS and Boehm titration results indicate that the oxygen elimination undergoes three distinctive stages(intermolecular dehydration, hydrogenation and decomposition reactions). The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700 °C. Benefiting from the stable electrochemical interface and the optimized porous structure, the as-obtained HAC-700 exhibit significantly suppressed self-discharge and leak current, with improved cycling stability, which is attributable to the stabilization of electrochemical interface between carbon surface and electrolyte. The result provides insights for rational design of surface chemistry for high-performance carbon electrode towards advanced energy storage. 展开更多
关键词 Starch-based activated carbon Oxygen functional groups Hydrogen thermal reduction Structural evolution Organic electrolytes ELECTROCHEMISTRY
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Insights into the thermochemical evolution of maleic anhydride-initiated esterified starch to construct hard carbon microspheres for lithium-ion batteries 被引量:5
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作者 Ming-Xin Song Li-Jing Xie +6 位作者 Jia-Yao Cheng Zong-Lin Yi Ge Song Xiao-Yang Jia Jing-Peng Chen Quan-Gui Guo Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期448-458,I0012,共12页
Starch,as a typical polysaccharide with natural spherical morphology,is not only a preferred precursor for preparing carbon materials but also a model polymer for investigating thermochemical evolution mechanisms.Howe... Starch,as a typical polysaccharide with natural spherical morphology,is not only a preferred precursor for preparing carbon materials but also a model polymer for investigating thermochemical evolution mechanisms.However,starch usually suffers from severe foaming and low carbon yield during direct pyrolysis.Herein,we report a simple and eco-friendly dry strategy,by maleic anhydride initiating the esterification of starch,to design carbon microspheres against the starch foaming.Moreover,the infuence of ester grafting on the pyrolytic behavior of starch is also focused.The formation of ester groups in precursor guarantees the structural stability of starch-based intermediate because it can promote the accumulation of unsaturated species and accelerate the water elimination during pyrolysis.Meanwhile,the esterification and dehydration reactions greatly deplete the primary hydroxyl groups in the starch molecules and thus the rapid levoglucosan release is inhibited,which well keeps the spherical morphology of starch and ensures the high carbon yield.In further exploration as anode materials for Lithium-ion batteries,the obtained carbon microspheres exhibit good cyclability and rate performance with a reversible capacity of 444 m Ah g^(-1)at 50 m A g^(-1).This work provides theoretical fundamentals for the controllable thermal transformation of biomass towards wide applications. 展开更多
关键词 Maleic anhydride esterified starch Dry strategy Thermochemical evolution Hard carbon microspheres Lithium-ion batteries
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Molecular-scale controllable conversion of biopolymers into hard carbons towards lithium and sodium ion batteries: A review 被引量:4
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作者 Li-Jing Xie Cheng Tang +9 位作者 Ming-Xin Song Xiao-Qian Guo Xiao-Ming Li Jing-Xue Li Chong Yan Qing-Qiang Kong Guo-Hua Sun Qiang Zhang Fang-Yuan Su Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期554-569,I0016,共17页
Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. T... Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. The renewable biomass is a green and economically attractive carbon source to produce hard carbons. However, the chemical and structural complexity of biomass has plagued the understanding of evolution mechanism from organic precursors to hard carbons and the structure-property relationship.This makes it difficult to finely tune the microstructure of biomass-derived hard carbons, thus greatly restricting their high-performance applications. Most recently, the optimal utilization and controllable conversion of biomass-derived biopolymers(such as starch, cellulose and lignin) at the molecular level have become a burgeoning area of research to develop hard carbons for advanced batteries.Considering the principal source of carbonaceous materials is from biomass pyrolysis, we firstly overview the chemical structures and pyrolysis behaviors of three main biopolymers. Then, the controllable preparation of hard carbons using various physicochemical properties of biopolymers at the molecular level is systematically discussed. Furthermore, we highlight present challenges and further opportunities in this field. The Review will guide future research works on the design of sustainable hard carbons and the optimization of battery performance. 展开更多
关键词 Biomass-derived biopolymers Hard carbons Lithium ion batteries Sodium ion batteries CARBONIZATION
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A Universal Atomic Substitution Conversion Strategy Towards Synthesis of Large‑Size Ultrathin Nonlayered Two‑Dimensional Materials 被引量:2
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作者 Mei Zhao Sijie Yang +10 位作者 Kenan Zhang Lijie Zhang Ping Chen Sanjun Yang Yang Zhao Xiang Ding Xiaotao Zu Yuan Li Yinghe Zhao Liang Qiao Tianyou Zhai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第11期79-91,共13页
Nonlayered two-dimensional(2D)materials have attracted increasing attention,due to novel physical properties,unique surface structure,and high compatibility with microfabrication technique.However,owing to the inheren... Nonlayered two-dimensional(2D)materials have attracted increasing attention,due to novel physical properties,unique surface structure,and high compatibility with microfabrication technique.However,owing to the inherent strong covalent bonds,the direct synthesis of 2D planar structure from nonlayered materials,especially for the realization of large-size ultrathin 2D nonlayered materials,is still a huge challenge.Here,a general atomic substitution conversion strategy is proposed to synthesize large-size,ultrathin nonlayered 2D materials.Taking nonlayered CdS as a typical example,large-size ultrathin nonlayered CdS single-crystalline flakes are successfully achieved via a facile low-temperature chemical sulfurization method,where pre-grown layered CdI2 flakes are employed as the precursor via a simple hot plate assisted vertical vapor deposition method.The size and thickness of CdS flakes can be controlled by the CdI2 precursor.The growth mechanism is ascribed to the chemical substitution reaction from I to S atoms between CdI2 and CdS,which has been evidenced by experiments and theoretical calculations.The atomic substitution conversion strategy demonstrates that the existing 2D layered materials can serve as the precursor for difficult-to-synthesize nonlayered 2D materials,providing a bridge between layered and nonlayered materials,meanwhile realizing the fabrication of large-size ultrathin nonlayered 2D materials. 展开更多
关键词 Nonlayered 2D materials Large-size ultrathin CdS flakes Atomic substitution conversion Layered-nonlayered structural transformation
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Structural evolution of carbon aerogel microspheres by thermal treatment for high–power supercapacitors 被引量:1
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作者 Feng Li Lijing Xie +5 位作者 Guohua Sun Fangyuan Su Qingqiang Kong Yufang Cao Xiangyun Guo Chengmeng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期439-446,共8页
In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. Th... In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. The effects of heat-treatment temperature(HTT) on the CAM microstructure were systematically investigated by physical and chemical characterization. The electrical conductivity increased by up to 250 S/cm and mesopores with high electrolyte accessibility developed in the CAM with increasing HTT. However, the specific surface area(SSA) decreased for HTTs from 1000 to 1600 ℃. The results show that these two factors should be finely balanced for further applications in high power supercapacitors.The CAMs carbonized at 1000 ℃ had the highest SSA(1454 m^2/g), large mesoporous content(20%) and favorable conductivity(71 S/cm). They delivered a high energy density of 38.4 Wh/kg at a power density of 0.17 kW/kg. They retained an energy density of 25.5 Wh/kg even at a high power density of 10.2 kW/kg,and a good rate capability of 84% after 10,000 cycles. This performance is superior to, or at least comparable to, those of most reported carbon materials. 展开更多
关键词 Carbon aerogel microspheres Heat-treatment temperature Physical/chemical changes CONDUCTIVITY SUPERCAPACITOR
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Converting furfural residue wastes to carbon materials for high performance supercapacitor 被引量:1
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作者 Xiaoying Guo Xusheng Zhang +2 位作者 Yingxiong Wang Xiaodong Tian Yan Qiao 《Green Energy & Environment》 SCIE EI CSCD 2022年第6期1270-1280,共11页
Sustainable development based on the value-added utilization of furfural residues(FRs)is an effective way to achieve a profitable circular economy.This comprehensive work highlights the potential of FRs as precursor t... Sustainable development based on the value-added utilization of furfural residues(FRs)is an effective way to achieve a profitable circular economy.This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors(SCs).To improve the electrochemical performance of FR-based carbon materials,a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed.More defects could be obtained after methanol treatment,which is incline to optimize textural structure.The activated methanol treated FR-based carbon materials(AFRMs)possess high specific surface area(1753.5 m^(2) g^(-1)),large pore volume(0.85 cm^(3) g^(-1)),interconnected micro/mesoporous structure,which endow the AFRMs with good electrochemical performance in half-cell(326.1 F g^(-1) at 0.1 Ag^(-1),189.4 Fg^(-1) at 50 A g^(-1) in 6 mol L^(-1) KOH).The constructed symmetric SCs based on KOH,KOH–K_(3)Fe(CN)_(6) and KOH-KI electrolyte deliver energy density up to 8.9,9.9 and 10.6 Wh kg^(-1) with a capacitance retention of over 86%after 10,000 cycles.Furthermore,the self-discharge can be restrained by the addition of K_(3)Fe(CN)_(6) and KI in KOH electrolyte.This study provides an effective approach for high-valued utilization of FR waste. 展开更多
关键词 Furfural residue METHANOL Porous carbon materials Electrolyte additives SUPERCAPACITOR
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Preparation and promising optoelectronic applications of lead halide perovskite patterned structures:A review 被引量:2
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作者 Shangui Lan Baojun Pan +5 位作者 Ying Liu Zhixiang Zhang Lijie Zhang Bin Yu Yanjun Fang Peijian Wang 《Carbon Energy》 SCIE EI CAS CSCD 2023年第10期91-115,共25页
Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform f... Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform for fundamental science research and applications.Patterned structures based on lead halide perovskites have much more novel properties compared with their more commonly seen bulk-,micro-,and nano-crystals,such as improvement in antireflection,light-scattering effects,and light absorption,as a result of their adjustability of spatial distributions.However,there are many challenges yet to be resolved in this field,such as insufficient patterned resolution,imperfect crystal quality,complicated preparation process,and so on.To pave the way to solve these problems,we provide a systematic presentation of current methods for fabricating lead halide perovskite patterned structures,including thermal imprint,use of etching films,two-step vapor-phase growth,template-confined solution growth,and seed-assisted growth.Furthermore,the advantages and disadvantages of these methods are elaborated in detail.In addition,thanks to the extraordinary properties of lead halide perovskite patterned structures,a variety of potential applications in optics and optoelectronics of these structures are described.Lastly,we put forward existing challenges and prospects in this exciting field. 展开更多
关键词 fabrication lead halide perovskites optics OPTOELECTRONICS patterned structures photovoltaics
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Sustainable Lignin-Derived Carbon as Capacity-Kinetics Matched Cathode and Anode towards 4.5 V High-Performance Lithium-Ion Capacitors 被引量:2
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作者 Fangyan Liu Pengfei Lu +7 位作者 Ying Zhang Feng Su Liangzhu Zhang Shuanghao Zheng Xiong Zhang Fangyuan Su Yanwei Ma Zhongshuai Wu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期98-105,共8页
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
关键词 capacity-kinetics matching defective hierarchical porous carbons high mass loading high power density Li-ion capacitors
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Edge atomic Fe sites decorated porous graphitic carbon as an efficient bifunctional oxygen catalyst for Zinc-air batteries
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作者 Ruihui Gan Yali Wang +3 位作者 Xiangwu Zhang Yan Song Jingli Shi Chang Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期602-611,I0014,共11页
The development of advanced bifunctional oxygen electrocatalysts for oxygen reduction and evolution reactions(ORR and OER) is critical to the practical application of zinc-air batteries(ZABs). Herein, a silica-assiste... The development of advanced bifunctional oxygen electrocatalysts for oxygen reduction and evolution reactions(ORR and OER) is critical to the practical application of zinc-air batteries(ZABs). Herein, a silica-assisted method is reported to integrate numerous accessible edge Fe-Nx sites into porous graphitic carbon(named Fe-N-G) for achieving highly active and robust oxygen electrocatalysis. Silica facilitates the formation of edge Fe-Nx sites and dense graphitic domains in carbon by inhibiting iron aggregation.The purification process creates a well-developed mass transfer channel for Fe-N-G. Consequently,Fe-N-G delivers a half-wave potential of 0.859 V in ORR and an overpotential of 344 m V at10 m A cm^(-2)in OER. During long-term operation, the graphitic layers protect edge Fe-Nx sites from demetallation in ORR and synergize with Fe OOH species endowing Fe-N-G with enhanced OER activity.Density functional theory calculations reveal that the edge Fe-Nx site is superior to the in-plane Fe-Nx site in terms of OH* dissociation in ORR and OOH* formation in OER. The constructed ZAB based on Fe-N-G cathode shows a higher peak power density of 133 m W cm^(-2)and more stable cycling performance than Pt/C + RuO2counterparts. This work provides a novel strategy to obtain high-efficiency bifunctional oxygen electrocatalysts through space mediation. 展开更多
关键词 Bifunctionality EdgeFe-Nxsites Oxygen catalysis Graphitic domains Zinc-air batteries
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New insights into the effect of hard carbons microstructure on the diffusion of sodium ions into closed pores 被引量:1
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作者 Mingxin Song Lijing Xie +3 位作者 Fangyuan Su Zonglin Yi Quangui Guo Cheng-Meng Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期155-160,共6页
Closed pores formed in hard carbons play an essential role in sodium storage at plateau region.However,the effect of different structural features on the diffusion of sodium ions into closed pores remains unclear.Here... Closed pores formed in hard carbons play an essential role in sodium storage at plateau region.However,the effect of different structural features on the diffusion of sodium ions into closed pores remains unclear.Herein,a precursor reconstruction strategy is conducted to regulate carbon microstructures including interlayer spacing,defect concentration,and closed pore volume by changing the ratio of aromatic and polysaccharide components.Aromatic structure parts tend to develop disordered carbons with fewer defects,larger interlayer spacing,and smaller closed pore volume,while polysaccharide components prefer to form disordered carbons with more defects,smaller interlayer spacing,and larger closed pore volume.Through the correlation analysis of microstructure features and the sodium storage capacity below 0.1 V.It finds that the intercalation capacity is proportional to the ratio of pseudo-graphitic domains,whereas the pore filling capacity appeared at lower potential gradually decreases with the increasing defect concentration due to homo-ionic repulsion effect,without linear correlation with shortrange microcrystalline and closed pore volume.The optimized sample with suitable interlayer spacing and defect concentration exhibits a high plateau capacity of 241.7 m Ah/g.This work provides insights into the exploitation of closed pore sodium storage performance. 展开更多
关键词 Precursor reconstruction Hard carbons Structural features Closed pore filling Sodium-ion batteries
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Electron-distribution control via Pt/NC and MoC/NC dual junction:Boosted hydrogen electro-oxidation and theoretical study 被引量:1
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作者 Feng Zhou Xiaofeng Ke +8 位作者 Yihuang Chen Mei Zhao Yun Yang Youqing Dong Chao Zou Xi’an Chen Huile Jin Lijie Zhang Shun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期513-520,I0011,共9页
The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to ... The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO. 展开更多
关键词 Hydrogen oxidation reaction Dual junctions CO-tolerance PLATINUM
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