泡沫镍负载Fe2O3@Ni3S2纳米线网状结构电极的制备及其电催化析氧性能

通过两步水热法制备泡沫镍(NF)负载Fe_2O_3纳米粒子@Ni_3S_2纳米线网状结构电极(Fe_2O_3@Ni_3S_2/NF)。运用X射线衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、N_2吸附-脱附测试等方法对电极材料的物相和微观结构特征等进行了表征。水热条件下原位表面化学刻蚀生成的Ni_3S_2纳米线与三维多孔NF基体间拥有强结合力和低界面电阻,Fe_2O_3粒子均匀分布在纳米线的表面。在1 mol·L~(-1)的KOH溶液中,运用线性扫描伏安测试(LSV)、计时电位法、电化学交流阻抗测试(EIS)等对电极的电催化析氧(OER)性能进行了测试。结果表明:在100 mA·cm~(-2)的超高电流密度下,Fe_2O_3@Ni_3S_2/NF电极的OER过电势仅为223 mV,比Ni_3S_2/NF材料的过电势降低了285 mV;经过10 h计时电位测试,性能保持率高达80%。

Preparation of Nickel Foam Supported Fe2O3@Ni3S2 Nanowires Network Electrode and Electrocatalytic Oxygen Evolution Performance

A two-step hydrothermal method was used to prepare nickel foam (NF) supported Fe₂O₃ nanoparticles@Ni₃S₂ nanowires 3D network electrode (Fe₂O₃@Ni₃S₂/NF). The crystal phase and microstructure features of the products were characterized in detail by using some characterization techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and N₂ adsorption-desorption measurement and so on. The in situ surface chemical etching process under hydrothermal conditions leads to the generation of Ni₃S₂ nanowires 3D network that binds to NF firmly with relatively low interfacial resistances. In an aqueous electrolyte of 1 mol·L^-1 KOH, the electrocatalytic oxygen evolution reaction (OER) performance of the obtained electrodes was tested by linear sweep voltammetry (LSV), chronopotentiometry, and electrochemical impedance test (EIS). At a ultrathigh current density of 100 mA·cm^-2, Fe₂O₃@Ni₃S₂/NF electrode showed a low OER overpotential of only 223 mV, which was 285 mV lower than that of Ni₃S₂/NF electrode (before growth of Fe₂O₃). These excellent properties are attributed to the faster reaction kinetics and smaller charge transfer impedance of Fe₂O₃@Ni₃S₂/NF electrode comparing with Ni₃S₂/NF.