AC/Ni-Co复合电极材料的制备及其催化析氢性能

采用复合电沉积法制备了AC(活性炭) / Ni-Co 复合电极。XRD 和SEM 测试结果表明, AC 微粒的复合未改变Ni-Co 合金电极的物相结构, 但使镀层的表面粗糙度和真实表面积增大。通过稳态阴极极化曲线和电化学交流阻抗技术考察了不同电极在1 mol·L-1 NaOH 溶液中的催化析氢性能, 结果表明, 镀液中AC 含量为3 g·L-1时所制备的AC/ Ni-Co 复合电极较Ni 电极和Ni-Co 合金电极具有更高的催化析氢活性, 电流密度为30 mA·cm-2时, 析氢反应极化电位分别比Ni 电极和Ni-Co 合金电极正移230 mV 和140 mV , 表观交换电流密度分别是Ni 电极和Ni-Co 合金电极的42 倍和9 倍, 复合电极催化析氢性能的提高主要归因于电极真实表面积的增大。 

Preparation and property for hydrogen evolution of AC ( activated char) /Ni-Co composite electrode materials

The AC/ Ni-Co composite elect rode was prepared by means of composite-elect rodeposition. The surfacemorphology and microst ructure of the elect rode coating were observed by XRD and SEM. The result s show that thecomposition of AC does not change the crystal st ructure of the Ni-Co alloy elect rode , but the surface roughness andreal surface area of the coatings increase. Catalytic abilities for hydrogen evolution of different elect rodes in1 mol·L-1 NaOH solution were evaluated on the basis of elect rochemical steady-state polarization curves andalternating current impedance spect rum technology. The result s show that the AC/ Ni-Co composite elect rode ( theamount of AC is 3 g·L-1 in bath ) is catalytically more active than the Ni and Ni-Co alloy elect rode. The polarizationpotential for hydrogen evolution of the composite elect rode is 230 mV lower than that of the Ni elect rode and is140 mV lower than that of the Ni-Co alloy elect rode at the current density of 0. 03 A·cm-2 . The apparent exchangecurrent density of the composite elect rode is 30 times as much as that of Ni elect rode , and 6 times that of the Ni-Coalloy elect rode. The increasing catalytic activity for hydrogen evolution of the AC/ Ni-Co composite elect rode ismainly due to the increase in the real surface area of the elect rode.