Enabling highly reversible sodium(Na) metal anodes in a polymer electrolyte(PE) system is critical for realizing next-generation batteries with lower cost,higher energy,and improved safety.However,the uneven Na deposi...Enabling highly reversible sodium(Na) metal anodes in a polymer electrolyte(PE) system is critical for realizing next-generation batteries with lower cost,higher energy,and improved safety.However,the uneven Na deposition and high Na/PE interphase resistance lead to poor reversibility and short cycle life of Na metal anodes.To tackle these problems,here a variety of metal nanoparticles(M-np,M=Al,Sn,In or Au) are deposited onto copper(Cu) foils to synthesize binder-free M-np@Cu substrates for Na plating/stripping.Notably,the Au-np@Cu substrate provides abundant preferential nucleation/growth sites,decreasing Na nucleation barrier and thus promoting uniform Na deposition.Accordingly,stable Na metal anodes are achieved with high reversible capacities,long cycle life,and high usage of Na.With the Au-np@Cu/Na anode and PE,the full cell using a commercial bulk sulfur cathode exhibits a reversible capacity of>400 mAh g^(-1) with near-100% Coulombic efficiency over 200 cycles.展开更多
2D transition metal carbides,carbonitrides,and nitrides known as MXenes possess high electrical conductivity,large redox active surface area,rich surface chemistry,and tunable structures.Benefiting from these exceptio...2D transition metal carbides,carbonitrides,and nitrides known as MXenes possess high electrical conductivity,large redox active surface area,rich surface chemistry,and tunable structures.Benefiting from these exceptional chemical and physical properties,the applications of MXenes for electrochemical energy storage and conversion have attracted increasing research interests around the world.Notably,the electrochemical performances of MXenes are directly dependent on their synthesis conditions,interfacial chemistries and structural configurations.In this review,we summarize the synthesis techniques of MXenes,as well as the recent advances in the interfacial structure design of MXene-based nanomaterials for electrochemical energy storage and conversion applications.Additionally,we provide an in-depth discussion on the relationship between interfacial structure and electrochemical performance from the perspectives of energy storage and electrocatalysis mechanisms.Finally,the challenges and insights for the future research of interfacial structure design of MXenes are outlined.展开更多
基金support from the Early Career Faculty grant (80NSSC18K1514) from NASA’s Space Technology Research Grants Programsupport from the startup funds at Thayer School of Engineering,Dartmouth College。
文摘Enabling highly reversible sodium(Na) metal anodes in a polymer electrolyte(PE) system is critical for realizing next-generation batteries with lower cost,higher energy,and improved safety.However,the uneven Na deposition and high Na/PE interphase resistance lead to poor reversibility and short cycle life of Na metal anodes.To tackle these problems,here a variety of metal nanoparticles(M-np,M=Al,Sn,In or Au) are deposited onto copper(Cu) foils to synthesize binder-free M-np@Cu substrates for Na plating/stripping.Notably,the Au-np@Cu substrate provides abundant preferential nucleation/growth sites,decreasing Na nucleation barrier and thus promoting uniform Na deposition.Accordingly,stable Na metal anodes are achieved with high reversible capacities,long cycle life,and high usage of Na.With the Au-np@Cu/Na anode and PE,the full cell using a commercial bulk sulfur cathode exhibits a reversible capacity of>400 mAh g^(-1) with near-100% Coulombic efficiency over 200 cycles.
基金Zhejiang University of TechnologyNatural Science Foundation of Zhejiang Province,Grant/Award Number:LD18E020003+1 种基金National Natural Science Foundation of China,Grant/Award Number:51722210Dartmouth College。
文摘2D transition metal carbides,carbonitrides,and nitrides known as MXenes possess high electrical conductivity,large redox active surface area,rich surface chemistry,and tunable structures.Benefiting from these exceptional chemical and physical properties,the applications of MXenes for electrochemical energy storage and conversion have attracted increasing research interests around the world.Notably,the electrochemical performances of MXenes are directly dependent on their synthesis conditions,interfacial chemistries and structural configurations.In this review,we summarize the synthesis techniques of MXenes,as well as the recent advances in the interfacial structure design of MXene-based nanomaterials for electrochemical energy storage and conversion applications.Additionally,we provide an in-depth discussion on the relationship between interfacial structure and electrochemical performance from the perspectives of energy storage and electrocatalysis mechanisms.Finally,the challenges and insights for the future research of interfacial structure design of MXenes are outlined.