Developing efficient,stable and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water splitting.Herein,the promising and highly efficient porous CoCrF...Developing efficient,stable and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water splitting.Herein,the promising and highly efficient porous CoCrFeNiMo high entropy alloys(HEAs)were prepared by microwave sintering using Mg space holder.Owing to unique properties of high entropy alloys and abundant active surface area,the porous CoCrFeNiMo-20 Mg exhibits excellent catalytic performance and prominent electrochemical stability with a low overpotential of 220 mV to reach current density of 10 mA cm^(-2),a small Tafel slope of 59.0 mV dec^(-1) and long-term durability for 24 h in 1.0 M KOH.The results of microstructure and element states indicate that crystal defects,porous structure and villous hydroxides are the reasons for high OER performance of the CoCrFeNiMo.This work not only provides a new way to prepare electrocatalysts,but also proves the important application of high entropy alloys in functional materials.展开更多
This paper describes a detailed analysis of the dependence of Raman scattering intensity on the polarization of the incident and inelastically scattered light in PbSc_(0.5)Nb_(0.5)O_(3)(PSN)single crystals and epitaxi...This paper describes a detailed analysis of the dependence of Raman scattering intensity on the polarization of the incident and inelastically scattered light in PbSc_(0.5)Nb_(0.5)O_(3)(PSN)single crystals and epitaxially compressed thin films grown on(100)-oriented MgO substrates.It is found that there are significant differences between the properties of the crystals and films,and that these differences can be attributed to the anticipated structural differences between these two forms of the same material.In particular,the scattering characteristics of the oxygen octahedra breathing mode near 810 cm^(-1) indicate a ferroelectric state for the crystals and a relaxor state for the films,which is consistent with the dielectric behaviors of these materials.展开更多
基金The authors gratefully acknowledge the financial support of the project from the National Natural Science Foundation of China(51862026)the Natural Science Foundation of Jiangxi Province(20202ACBL214011,20192ACBL21048)the Aeronautical Science Foundation of China(2017ZF56027)。
文摘Developing efficient,stable and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water splitting.Herein,the promising and highly efficient porous CoCrFeNiMo high entropy alloys(HEAs)were prepared by microwave sintering using Mg space holder.Owing to unique properties of high entropy alloys and abundant active surface area,the porous CoCrFeNiMo-20 Mg exhibits excellent catalytic performance and prominent electrochemical stability with a low overpotential of 220 mV to reach current density of 10 mA cm^(-2),a small Tafel slope of 59.0 mV dec^(-1) and long-term durability for 24 h in 1.0 M KOH.The results of microstructure and element states indicate that crystal defects,porous structure and villous hydroxides are the reasons for high OER performance of the CoCrFeNiMo.This work not only provides a new way to prepare electrocatalysts,but also proves the important application of high entropy alloys in functional materials.
基金supported by the Czech Science Foundation(Projects CSF 15-04121S and 15-15123S)the United Stated Office of Naval Research(Grant No.N00014-12-1-1045)the Natural Science&Engineering Research Council of Canada(NSERC).
文摘This paper describes a detailed analysis of the dependence of Raman scattering intensity on the polarization of the incident and inelastically scattered light in PbSc_(0.5)Nb_(0.5)O_(3)(PSN)single crystals and epitaxially compressed thin films grown on(100)-oriented MgO substrates.It is found that there are significant differences between the properties of the crystals and films,and that these differences can be attributed to the anticipated structural differences between these two forms of the same material.In particular,the scattering characteristics of the oxygen octahedra breathing mode near 810 cm^(-1) indicate a ferroelectric state for the crystals and a relaxor state for the films,which is consistent with the dielectric behaviors of these materials.
