Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a...Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.展开更多
The microstructural formation of the semi-solid AlSi7Mg alloy stirred by electromagnetic field is investigated together withthe tempeatre field of the stirred melt at continuously cooling. A impoat kinetic factor for ...The microstructural formation of the semi-solid AlSi7Mg alloy stirred by electromagnetic field is investigated together withthe tempeatre field of the stirred melt at continuously cooling. A impoat kinetic factor for primny a-Al nucleation is proposed. It isfound that a low temperatUre gradient exists in the electromagnetic stirred melt. This is why the first dendritic arms and secondary de-ndritic arms are refmed. Experimefltal results also show that the root remelting of secontw dendritic arms is an twortat mechanismfor the primary α-Al refmement. Strong electromagnetic stirring greatly reduces the composition supercooling in the melt and eliminatesprefedrig growth of the first dendritic arms. Therefore, many rosettes or spherical Primary α-Al phase particles form finally.展开更多
基金supported by Research Grants of the NRF(2023R1A2C2003823,RS-2024-00405818)funded by the National Research Foundation under the Ministry of Science,ICT&Future,Korea。
文摘Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.
文摘The microstructural formation of the semi-solid AlSi7Mg alloy stirred by electromagnetic field is investigated together withthe tempeatre field of the stirred melt at continuously cooling. A impoat kinetic factor for primny a-Al nucleation is proposed. It isfound that a low temperatUre gradient exists in the electromagnetic stirred melt. This is why the first dendritic arms and secondary de-ndritic arms are refmed. Experimefltal results also show that the root remelting of secontw dendritic arms is an twortat mechanismfor the primary α-Al refmement. Strong electromagnetic stirring greatly reduces the composition supercooling in the melt and eliminatesprefedrig growth of the first dendritic arms. Therefore, many rosettes or spherical Primary α-Al phase particles form finally.
