Efficient,stable and economical catalysts play a crucial role in enhancing the kinetics of slow oxygen reduction reactions(ORR)in Aluminum-air batteries.Among the potential next-generation candidates,Ag catalysts are ...Efficient,stable and economical catalysts play a crucial role in enhancing the kinetics of slow oxygen reduction reactions(ORR)in Aluminum-air batteries.Among the potential next-generation candidates,Ag catalysts are promising due to their high activity and low cost,but weaker oxygen adsorption has hindered industrialization.To address this bottleneck,Ag-alloying has emerged as a principal strategy.In this work,we successfully prepared Ag-Cu nanoparticles(NPs)with a rich eutectic phase and uniform dispersion structure using plasma evaporation.The increased solid solution of Ag and Cu led to changes in the electronic structure,resulting in an upward shift of the d-band center,which significantly improved oxygen adsorption.The combination of Ag and Cu in the NPs synergistically enhanced the adsorption of Ag and the desorption of Cu.Density functional theory(DFT)calculations revealed that Ag-Cu25 NPs exhibited the smallest limiting reaction barrier,leading to increased ORR activity.To further optimize the catalyst’s performance,we utilized N-doped porous nanocarbon(N-PC)with high electrical conductivity and abundant mesoporous channels as the support for the Ag-Cu NPs.The N-PC support provided optimal mass transfer carriers for the highly active Ag-Cu25 NPs.As a result,the Ag-Cu25/NPC catalyst displayed excellent ORR activity in alkaline media,with a half-wave potential(E_(1/2))of 0.82 V.Furthermore,the Al-air battery incorporating the Ag-Cu25/NPC catalyst exhibited outstanding electrochemical performance.It demonstrated high open-circuit voltages of 1.89 V and remarkable power densities of 193 m W cm^(-2).The battery also sustained a high current output and maintained a stable high voltage for 120 hours under mechanical charging,showcasing its significant potential for practical applications.展开更多
基金supported by the Fundamental Research Funds for the Central Universities of China(DUT20-LAB307)the Supercomputing Center of Dalian University of Technology。
文摘Efficient,stable and economical catalysts play a crucial role in enhancing the kinetics of slow oxygen reduction reactions(ORR)in Aluminum-air batteries.Among the potential next-generation candidates,Ag catalysts are promising due to their high activity and low cost,but weaker oxygen adsorption has hindered industrialization.To address this bottleneck,Ag-alloying has emerged as a principal strategy.In this work,we successfully prepared Ag-Cu nanoparticles(NPs)with a rich eutectic phase and uniform dispersion structure using plasma evaporation.The increased solid solution of Ag and Cu led to changes in the electronic structure,resulting in an upward shift of the d-band center,which significantly improved oxygen adsorption.The combination of Ag and Cu in the NPs synergistically enhanced the adsorption of Ag and the desorption of Cu.Density functional theory(DFT)calculations revealed that Ag-Cu25 NPs exhibited the smallest limiting reaction barrier,leading to increased ORR activity.To further optimize the catalyst’s performance,we utilized N-doped porous nanocarbon(N-PC)with high electrical conductivity and abundant mesoporous channels as the support for the Ag-Cu NPs.The N-PC support provided optimal mass transfer carriers for the highly active Ag-Cu25 NPs.As a result,the Ag-Cu25/NPC catalyst displayed excellent ORR activity in alkaline media,with a half-wave potential(E_(1/2))of 0.82 V.Furthermore,the Al-air battery incorporating the Ag-Cu25/NPC catalyst exhibited outstanding electrochemical performance.It demonstrated high open-circuit voltages of 1.89 V and remarkable power densities of 193 m W cm^(-2).The battery also sustained a high current output and maintained a stable high voltage for 120 hours under mechanical charging,showcasing its significant potential for practical applications.
