聚苯胺包覆硒化镍的制备与析氢性能

Preparation and hydrogen evolution performance of polyaniline coated NiSe electrode

采用水热和电化学沉积两步法制备泡沫镍(NF)负载的聚苯胺(PANI)包覆硒化镍(NiSe)析氢电极(PANI/NiSe/NF),利用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、X射线光电子能谱仪(XPS)以及电化学测试等手段对材料进行形貌、组成及电化学性能表征。结果表明,以氯化镍为镍源,用水热法可制备出泡沫镍负载的针状NiSe,使用导电聚合物聚苯胺包覆不改变其形貌。PANI/NiSe/NF电极的双电层电容为12560μF/cm^(2),大于NiSe/NF电极的9200μF/cm^(2),拥有更大的电化学活性面积,其析氢起始过电位比未包覆时降低了58 mV,Tafel斜率为133 mV/dec。电流密度为10 mA/cm^(2)时,PANI/NiSe/NF电极的析氢过电位为203 mV,展示出优异的析氢催化活性。导电聚合物PANI的包覆不仅可提高硒化镍电极的析氢活性,而且可减小电荷转移电阻,加快电荷转移速率,并显著提高电极稳定性。

A two-step method of hydrothermal and electrochemical deposition was used to prepare a polyaniline-coated nickel selenide hydrogen evolution electrode(PANI/NiSe/NF)supported on nickel foam.The morphology,constitution and electrochemical properties of the as-prepared specimen were characterized by using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and electrochemical tests.The results show that using nickel chloride as the nickel source,the needle-like NiSe supported on nickel foam was successfully prepared by hydrothermal method,and the coating of conductive polymer polyaniline has not change its morphology.The electric double layer capacitance of PANI/NiSe/NF electrode is 12560μF/cm^(2),which is larger than that of the NiSe/NF electrode 9200μF/cm^(2).PANI/NiSe/NF electrode has a larger electrochemically active area,58 mV lower initial over potential for hydrogen evolution than uncoated NiSe/NF electrode and 133 mV/dec Tafel slope.PANI/NiSe/NF electrode exhibites a hydrogen evolution over potential of 203 mV at current density of 10 mA/cm^(2),showing excellent hydrogen evolution catalytic activity.The coating of the conductive polymer PANI can not only improve the hydrogen evolution activity of NiSe/NF electrode,but also reduce the charge transfer resistance,and accelerate the charge transfer rate,and significantly improved the electrode stability.