The accelerated arriving of 5G era has brought a new round of intelligent transformation which will completely emancipate smart terminal devices.While the subsequent deleterious effect of electromagnetic wave on elect...The accelerated arriving of 5G era has brought a new round of intelligent transformation which will completely emancipate smart terminal devices.While the subsequent deleterious effect of electromagnetic wave on electronic devices is increasingly serious,driving the growth of next-generation electromagnetic wave absorbents.As a tactful combination of components and structures,three-dimensional(3D)macroscopic absorbents with fascinating synergy afford exceptional electromagnetic wave absorption,and tremendous efforts have been devoted to this investigation.However,in terms of macroscopic absorbents and their synergistic effect,few reviews are proposed to comb the latest achievements and detailed synergy.This review article focuses on the synergistic effect of macro-architectured absorbents mainly including structure-induced synergy,structure-components synergy,and multiple-components induced synergy.And then the potential construction principles and strategies of macroscopic absorbents are combed.Significantly,the key information for structures and components manipulation including nano-micro design and components regulation is further dissected by critically selected cutting-edge 3D macroscopic absorbents.Moreover,a brief summary of multifunctional electromagnetic wave absorbents(EWAs)-based macroscopic structures is presented.Finally,the development prospects and challenges of these materials are discussed.展开更多
The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challen...The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challenge.Herein,we reported an effective method to synthesize cobalt-nitrogen doped mesoporous carbon-based bifunctional oxygen electrocatalyst with controllable phosphorus content(Co-N-P_(X)-MC,X=0.5,1.0,1.5,2.0).The mesoporous carbon substrate endowed the asprepared samples with more exposed active surface(236.50 m^(2)·g^(−1))and the most appropriate doping ratio of phosphorus had been investigated to be 1.5(Co-N-P1.5-MC).For ORR,Co-N-P1.5-MC exhibited excellent catalytic activity with more positive onset potential(1.01 V)and half-wave potential(0.84 V)than the other samples.For OER,Co-N-P1.5-MC also showed a low overpotential of 415 mV.Combining experimental results and density-functional theory(DFT)calculations,the outstanding bifunctional catalytic performance of Co-N-P1.5-MC was due to the synergistic cooperation between the P and N dopants,which could reduce the reaction barriers and was favorable for ORR and OER.Moreover,the Zn-air battery using Co-N-P1.5-MC as the cathode showed remarkable battery performance with high stability(could operate stably for over 160 h at 10 mA·cm^(−2))and maximum power density(119 mW·cm^(−2)),demonstrating its potential for practical applications.This work could provide significant enlightenment towards the design and construction of bifunctional oxygen electrocatalyst for next-generation electrochemical devices.展开更多
Three-dimensional (3D) porous carbon-based materials with tunable composition and microstructure are of great interest for the development of oxygen involved electrocatalytic reactions. Here, we report the synthesis o...Three-dimensional (3D) porous carbon-based materials with tunable composition and microstructure are of great interest for the development of oxygen involved electrocatalytic reactions. Here, we report the synthesis of 3D porous carbon-based electrocatalyst by self-assembling Co-metal organic frameworks (MOF) building blocks on graphene via a layer-by-layer technique. Precise control of the structure and morphology is achieved by varying the MOF layer to tune the electrocatalytic properties. The as-produced electrocatalyst exhibits an excellent catalytic activity for the oxygen reduction reaction in 0.1molL^-1 KOH, showing a high onset potential of 0.963V vs. reversible hydrogen electrode (RHE) and a low tafel slope of 54mVdec^-1, compared to Pt/C (0.934V and 52mVdec^-1, respectively). Additionally, it shows a slightly lower potential vs. RHE (1.72V) than RuO2 (1.75V) at 10mAcm^-2 in an alkaline electrolyte. A rechargeable Zn-air battery based on the as-produced 3D porous catalyst demonstrates a high peak power density of 119mWcm^-2 at a cell voltage of 0.578V while retaining an excellent stability over 250 charge-discharge cycles.展开更多
The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/el...The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.展开更多
基金supported by the National Natural Science Foundation of China(No.52274362)the Doctorial Foundation of Henan University of Technology(Nos.2021BS030 and 2020BS030)+5 种基金the Key R&D projects of Henan Province(No.221111230800)the Innovative Funds Plan of Henan University of Technology(No.2021ZKCJ05)the Key Scientific and Technological Research Projects in Henan Province(No.222102240091)the Natural Science Foundation from the Department of Science and Technology of Henan Province(No.232300420309)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Key Laboratory of Engineering Dielectrics and Its Application(Harbin University of Science and Technology),Ministry of Education.
文摘The accelerated arriving of 5G era has brought a new round of intelligent transformation which will completely emancipate smart terminal devices.While the subsequent deleterious effect of electromagnetic wave on electronic devices is increasingly serious,driving the growth of next-generation electromagnetic wave absorbents.As a tactful combination of components and structures,three-dimensional(3D)macroscopic absorbents with fascinating synergy afford exceptional electromagnetic wave absorption,and tremendous efforts have been devoted to this investigation.However,in terms of macroscopic absorbents and their synergistic effect,few reviews are proposed to comb the latest achievements and detailed synergy.This review article focuses on the synergistic effect of macro-architectured absorbents mainly including structure-induced synergy,structure-components synergy,and multiple-components induced synergy.And then the potential construction principles and strategies of macroscopic absorbents are combed.Significantly,the key information for structures and components manipulation including nano-micro design and components regulation is further dissected by critically selected cutting-edge 3D macroscopic absorbents.Moreover,a brief summary of multifunctional electromagnetic wave absorbents(EWAs)-based macroscopic structures is presented.Finally,the development prospects and challenges of these materials are discussed.
基金financially supported by the Natural Science Foundation of Department of Science and Technology of Henan Province (232102240038)the Research Project in School-level of Henan University of Technology (2020BS017)Henan Province Education Department Natural Science Research Item (21A480005)。
基金supported by the Henan Province Education Department Natural Science Research Item(No.21A480005)the Research Project at School-level of Henan University of Technology(No.2020BS017).
文摘The controllable construction of non-noble metal based bifunctional catalysts with high activities towards oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of great significance,but remains a challenge.Herein,we reported an effective method to synthesize cobalt-nitrogen doped mesoporous carbon-based bifunctional oxygen electrocatalyst with controllable phosphorus content(Co-N-P_(X)-MC,X=0.5,1.0,1.5,2.0).The mesoporous carbon substrate endowed the asprepared samples with more exposed active surface(236.50 m^(2)·g^(−1))and the most appropriate doping ratio of phosphorus had been investigated to be 1.5(Co-N-P1.5-MC).For ORR,Co-N-P1.5-MC exhibited excellent catalytic activity with more positive onset potential(1.01 V)and half-wave potential(0.84 V)than the other samples.For OER,Co-N-P1.5-MC also showed a low overpotential of 415 mV.Combining experimental results and density-functional theory(DFT)calculations,the outstanding bifunctional catalytic performance of Co-N-P1.5-MC was due to the synergistic cooperation between the P and N dopants,which could reduce the reaction barriers and was favorable for ORR and OER.Moreover,the Zn-air battery using Co-N-P1.5-MC as the cathode showed remarkable battery performance with high stability(could operate stably for over 160 h at 10 mA·cm^(−2))and maximum power density(119 mW·cm^(−2)),demonstrating its potential for practical applications.This work could provide significant enlightenment towards the design and construction of bifunctional oxygen electrocatalyst for next-generation electrochemical devices.
基金supported by the National Natural Science Foundation of China (51472187)
文摘Three-dimensional (3D) porous carbon-based materials with tunable composition and microstructure are of great interest for the development of oxygen involved electrocatalytic reactions. Here, we report the synthesis of 3D porous carbon-based electrocatalyst by self-assembling Co-metal organic frameworks (MOF) building blocks on graphene via a layer-by-layer technique. Precise control of the structure and morphology is achieved by varying the MOF layer to tune the electrocatalytic properties. The as-produced electrocatalyst exhibits an excellent catalytic activity for the oxygen reduction reaction in 0.1molL^-1 KOH, showing a high onset potential of 0.963V vs. reversible hydrogen electrode (RHE) and a low tafel slope of 54mVdec^-1, compared to Pt/C (0.934V and 52mVdec^-1, respectively). Additionally, it shows a slightly lower potential vs. RHE (1.72V) than RuO2 (1.75V) at 10mAcm^-2 in an alkaline electrolyte. A rechargeable Zn-air battery based on the as-produced 3D porous catalyst demonstrates a high peak power density of 119mWcm^-2 at a cell voltage of 0.578V while retaining an excellent stability over 250 charge-discharge cycles.
基金This work was supported by the National Natural Science Foundation of China(No.51976143)the National Key Research and Development Program of China(No.2018YFA0702001)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(No.XHD2020-002).
文摘The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.
基金supported by the National Natural Science Foundation of China (51976143)the National Key Research and Development Program of China (2018YFA0702001)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHD2020-002)。
