The establishment of reactive oxygen species(ROS) elimination sites in iron-nitrogen-carbon(Fe-N-C) electrocatalysts to achieve durable proton-exchange membrane fuel cells(PEMFCs) performance has attracted broad inter...The establishment of reactive oxygen species(ROS) elimination sites in iron-nitrogen-carbon(Fe-N-C) electrocatalysts to achieve durable proton-exchange membrane fuel cells(PEMFCs) performance has attracted broad interest. However, realizing ROS removal efficiency and oxygen reduction reaction(ORR) activity within a single system represents a significant challenge to date. Herein, we demonstrate uniform ROS elimination sites and ORR centers through an electrochemical reconstruction method on the parallel sites of Fe@Ce NC electrocatalyst for durable PEMFC. During the reconstruction process, the Fe sites can retain their original configuration. Meanwhile, the pristine Ce clusters will evolve into more efficient, highly dispersed sites.Furthermore, the reconstructed Fe and Ce sites exhibit favorable energy barriers for the ORR and ROS elimination pathways,respectively, thereby maintaining ORR activity and achieving high ROS tolerance. Consequently, the PEMFC assembled with our catalyst shows only a 2% decay in power density after the accelerated durability test. We anticipate that this parallel structure design will provide new insight into the development of more durable electrocatalysts for PEMFCs.展开更多
Nitrate pollution and carbon emissions,driven by anthropogenic nitrogen cycle imbalance and fossil fuel overuse,pose serious threats to environmental and human health.Electrocatalytic C–N coupling of CO_(2) with nitr...Nitrate pollution and carbon emissions,driven by anthropogenic nitrogen cycle imbalance and fossil fuel overuse,pose serious threats to environmental and human health.Electrocatalytic C–N coupling of CO_(2) with nitrogen-containing species offers a sustainable route for urea synthesis,contributing to nitrogen recycling and carbon neutrality.However,developing electrocatalysts with high activity,selectivity,and stability remains challenging.Recent advances in rationally designed copper(Cu)-based catalysts have deepened the understanding of C–N coupling mechanisms and structure-performance relationships.This review highlights recent progress in Cu-based electrocatalysts for urea synthesis(mainly for CO_(2) and nitrate coupling),focusing on three key strategies:electronic structure modulation,defect engineering,and multi-site synergy.The reaction pathways are first summarized,followed by discussions on catalyst design principles aimed at optimizing intermediate adsorption,lowering C–N coupling barriers,and facilitating proton-coupled electron transfer.In-situ characterizations are employed to elucidate the mechanistic roles of these strategies.Finally,the key challenges and future directions for the application of Cu-based catalysts are outlined.展开更多
基金supported by the National Key R&D Program of China (2022YFA1502903)the National Natural Science Foundation of China (21925110, 22201274, 21890750, 52130202, 12175234)+4 种基金the University Synergy Innovation Program of Anhui Province (GXXT-2022-007)the support from the Major/Innovative Program of Development Foundation of the Hefei Center for Physical Science and Technologythe support from the beamline 1W1B at the Beijing Synchrotron Radiation Facility (BSRF, Beijing, China)the BL14W1 and BL11B beamlines at the Shanghai Synchrotron Radiation Facility (SSRF, Shanghai China)the beamlines BL11U, BL10B, and BL12B of National Synchrotron Radiation Laboratory (NSRL, Hefei, China)。
文摘The establishment of reactive oxygen species(ROS) elimination sites in iron-nitrogen-carbon(Fe-N-C) electrocatalysts to achieve durable proton-exchange membrane fuel cells(PEMFCs) performance has attracted broad interest. However, realizing ROS removal efficiency and oxygen reduction reaction(ORR) activity within a single system represents a significant challenge to date. Herein, we demonstrate uniform ROS elimination sites and ORR centers through an electrochemical reconstruction method on the parallel sites of Fe@Ce NC electrocatalyst for durable PEMFC. During the reconstruction process, the Fe sites can retain their original configuration. Meanwhile, the pristine Ce clusters will evolve into more efficient, highly dispersed sites.Furthermore, the reconstructed Fe and Ce sites exhibit favorable energy barriers for the ORR and ROS elimination pathways,respectively, thereby maintaining ORR activity and achieving high ROS tolerance. Consequently, the PEMFC assembled with our catalyst shows only a 2% decay in power density after the accelerated durability test. We anticipate that this parallel structure design will provide new insight into the development of more durable electrocatalysts for PEMFCs.
基金the support from the National Key R&D Program of China (2020YFA0710000)the National Natural Science Foundation of China (22425201,22422203,22102054,22250006,22261160640,22202065,22472048)+1 种基金the China Postdoctoral Science Foundation (BX20200116,2020M682540,2023M741117)the Natural Science Foundation of Hunan Province (2023JJ10002,2023JJ40705,2024JJ5067,2024JJ6127)。
文摘Nitrate pollution and carbon emissions,driven by anthropogenic nitrogen cycle imbalance and fossil fuel overuse,pose serious threats to environmental and human health.Electrocatalytic C–N coupling of CO_(2) with nitrogen-containing species offers a sustainable route for urea synthesis,contributing to nitrogen recycling and carbon neutrality.However,developing electrocatalysts with high activity,selectivity,and stability remains challenging.Recent advances in rationally designed copper(Cu)-based catalysts have deepened the understanding of C–N coupling mechanisms and structure-performance relationships.This review highlights recent progress in Cu-based electrocatalysts for urea synthesis(mainly for CO_(2) and nitrate coupling),focusing on three key strategies:electronic structure modulation,defect engineering,and multi-site synergy.The reaction pathways are first summarized,followed by discussions on catalyst design principles aimed at optimizing intermediate adsorption,lowering C–N coupling barriers,and facilitating proton-coupled electron transfer.In-situ characterizations are employed to elucidate the mechanistic roles of these strategies.Finally,the key challenges and future directions for the application of Cu-based catalysts are outlined.
