非晶态硼化物Ni-Fe-Co-B的合成及电催化析氧性能

Synthesis of amorphous borides Ni-Fe-Co-B and electrocatalytic properties for oxygen evolution reaction

摘要:

电解水制氢是绿色氢能源研究中的热点课题。其中，析氧半反应较高的过电位是导致电解水动力学缓慢的主要原因。为了提高电解水制氢的效率，本文主要通过简单的液相合成方法，以硼氢化钠和过渡金属Ni，Fe，Co盐为原料，制备了非晶态的过渡金属硼化物Ni-Fe-Co-B，将其作为析氧半反应催化剂。对Ni-Fe-Co-B进行了SEM、TEM、XRD、XPS和电化学表征。结果表明，非晶态催化材料Ni-Fe-Co-B被成功合成，当n(Ni)∶n(Fe)∶n(Co)=1∶1∶1，电流密度为20 mA/cm2时，Ni-Fe-Co-B的过电位仅为299 mV，Tafel斜率为101 mV/dec。在0.47 V的恒电压测试下，Ni-Fe-Co-B具有12h以上的稳定性。

Abstract:

Hydrogen production by electrolysis of water is a hot topic in the research of green hydrogen energy, the high overpotential of the oxygen evolution reaction is the main reason for the slow kinetics of electrolysis of water. In order to improve the efficiency of hydrogen production by electrolysis of water, the amorphous transition metal boride Ni-Fe-Co-B was mainly prepared by simple liquid phase synthesis with sodium borohydride and transition metal Ni, Fe and Co salts as raw materials, using it as the oxygen evolution reaction catalyst. The materials were characterized by SEM, TEM, XRD, XPS and Electrochemical characterization. The results show that the amorphous catalytic material Ni-Fe-Co-B has been successfully synthesized, When n(Ni)∶n(Fe)∶n(Co)=1∶1∶1, the overpotential is only 299 mV and the Tafel slope is 101 mV/dec at current density of 20 mA/cm2. Under the constant voltage test of 0.47 V, Ni-Fe-Co-B has excellent stability of more than 12 h.