Photoelectrochemical(PEC)water splitting holds significant promise for sustainable energy harvesting that enables efficient conversion of solar energy into green hydrogen.Nevertheless,achievement of high performance i...Photoelectrochemical(PEC)water splitting holds significant promise for sustainable energy harvesting that enables efficient conversion of solar energy into green hydrogen.Nevertheless,achievement of high performance is often limited by charge carrier recombination,resulting in unsatisfactory saturation current densities.To address this challenge,we present a novel strategy for achieving ultrahigh current density by incorporating a bridge layer between the Si substrate and the NiOOH cocatalyst in this paper.The optimal photoanode(TCO/n-p-Si/TCO/Ni)shows a remarkably low onset potential of 0.92 V vs.a reversible hydrogen electrode and a high saturation current density of 39.6 mA·cm^(-2),which is about 92.7%of the theoretical maximum(42.7 mA·cm^(-2)).In addition,the photoanode demonstrates stable operation for 60 h.Our systematic characterizations and calculations demonstrate that the bridge layer facilitates charge transfer,enhances catalytic performance,and provides corrosion protection to the underlying substrate.Notably,the integration of this photoanode into a PEC device for overall water splitting leads to a reduction of the onset potential.These findings provide a viable pathway for fabricating highperformance industrial photoelectrodes by integrating a substrate and a cocatalyst via a transparent and conductive bridge layer.展开更多
Large-scale green hydrogen production technology,based on the electrolysis of water powered by renewable energy,relies heavily on non-precious metal oxygen evolution reactions(OER)electrocatalysts with high activity a...Large-scale green hydrogen production technology,based on the electrolysis of water powered by renewable energy,relies heavily on non-precious metal oxygen evolution reactions(OER)electrocatalysts with high activity and stability under industrial conditions(6 M KOH,60℃-80℃)at large current density.Here,we construct Fe and Co co-incorporated nickel(oxy)hydroxide(Fe_(2.5)Co_(2.5)Ni_(10)O_(y)H_(z)@NFF)via a multi-metal electrodeposition,which exhibits outstanding OER performance(overpotential:185 mV@10 mA cm^(-2)).Importantly,an overwhelming stability for more than 1100 h at 500 mA cm^(-2)under industrial conditions is achieved.Our combined experimental and computational investigation reveals the surface-reconstructedγ-NiOOH with a high valence state is the active layer,where the optimal(Fe,Co)co-incorporation tunes its electronic structure,changes the potential determining step,and reduces the energy barrier,leading to ultrahigh activity and stability.Our findings demonstrate a facile way to achieve an electrocatalyst with high performance for the industrial production of green hydrogen.展开更多
基金supported by Multi-Year Research Grants from the University of Macao(MYRG-GRG2023-00010-IAPME,MYRG-GRG2024-00038-IAPME,MYRG2022-00026-IAPME)the Science and Technology Development Fund(FDCT)from Macao SAR(0023/2023/AFJ,0050/2023/RIB2,006/2022/ALC,0087/2024/AFJ,0111/2022/A2).
文摘Photoelectrochemical(PEC)water splitting holds significant promise for sustainable energy harvesting that enables efficient conversion of solar energy into green hydrogen.Nevertheless,achievement of high performance is often limited by charge carrier recombination,resulting in unsatisfactory saturation current densities.To address this challenge,we present a novel strategy for achieving ultrahigh current density by incorporating a bridge layer between the Si substrate and the NiOOH cocatalyst in this paper.The optimal photoanode(TCO/n-p-Si/TCO/Ni)shows a remarkably low onset potential of 0.92 V vs.a reversible hydrogen electrode and a high saturation current density of 39.6 mA·cm^(-2),which is about 92.7%of the theoretical maximum(42.7 mA·cm^(-2)).In addition,the photoanode demonstrates stable operation for 60 h.Our systematic characterizations and calculations demonstrate that the bridge layer facilitates charge transfer,enhances catalytic performance,and provides corrosion protection to the underlying substrate.Notably,the integration of this photoanode into a PEC device for overall water splitting leads to a reduction of the onset potential.These findings provide a viable pathway for fabricating highperformance industrial photoelectrodes by integrating a substrate and a cocatalyst via a transparent and conductive bridge layer.
基金supported by the Science and Technology Development Fund(FDCT)from Macao SAR(0050/2023/RIB2,0023/2023/AFJ,006/2022/ALC,0111/2022/A2,0105/2023/RIA2)Multi-Year Research Grants(MYRG-GRG2023-00010-IAPME,and MYRG2022-00026-IAPME)from Research&Development Office at University of MacaoShenzhen-Hong Kong-Macao Science and Technology Research Programme(Type C)(SGDX20210823103803017)from Shenzhen.
文摘Large-scale green hydrogen production technology,based on the electrolysis of water powered by renewable energy,relies heavily on non-precious metal oxygen evolution reactions(OER)electrocatalysts with high activity and stability under industrial conditions(6 M KOH,60℃-80℃)at large current density.Here,we construct Fe and Co co-incorporated nickel(oxy)hydroxide(Fe_(2.5)Co_(2.5)Ni_(10)O_(y)H_(z)@NFF)via a multi-metal electrodeposition,which exhibits outstanding OER performance(overpotential:185 mV@10 mA cm^(-2)).Importantly,an overwhelming stability for more than 1100 h at 500 mA cm^(-2)under industrial conditions is achieved.Our combined experimental and computational investigation reveals the surface-reconstructedγ-NiOOH with a high valence state is the active layer,where the optimal(Fe,Co)co-incorporation tunes its electronic structure,changes the potential determining step,and reduces the energy barrier,leading to ultrahigh activity and stability.Our findings demonstrate a facile way to achieve an electrocatalyst with high performance for the industrial production of green hydrogen.
