Ni-Co-LaNi_5复合电极材料在碱性介质中的电催化析氢性能  

Electrocatalytic Behavior of the Codeposited Ni-Co-LaNi0_5 Coatings for Hydrogen Evolution in Alkaline Medium

作　　者：武刚[1] 李宁[1] 周德瑞[1] 

机构地区：[1]哈尔滨工业大学应用化学系,哈尔滨150001

出　　处：《无机化学学报》2003年第7期739-744,共6页Chinese Journal of Inorganic Chemistry

基　　金：山东省科技发展计划基金资助项目(No.2002014)。

摘　　要：Composite coatings of Ni Co LaNi5, prepared by electrolytic codepositon of Ni Co alloys and LaNi5 particles from a sulfamate electrolyte were investigated in view of its possible application as electrocatalytic materials for the hydrogen evolution reaction(HER). The surface morphology and microstructure of Ni Co LaNi5 coatings were observed by means of SEM and XRD. Electrocatalytic efficiency was evaluated on the basis of electrochemical steady state Tafel polarization and electrochemical impedance spectroscopy technology in 1mol· L- 1 NaOH solution. The results were compared with Ni Co and Ni electrodes. The real electrochemical area was estimated by apparent double layer capacitances to account for the large difference in roughness factor of the three surfaces. The values obtained for the apparent energy of activation were 32.48kJ· mol- 1,46.29kJ· mol- 1 and 57.03kJ· mol- 1 for the HER on the Ni Co LaNi5, Ni Co and Ni electrodes, respectively. The composite coatings Ni Co LaNi5 is catalytically more active than Ni and Ni Co electrodes due to the increase in its real surface areas and the decrease in the apparent energy of activation caused by electrocatalytic synergistic effect of the Ni Co alloy and the rare earth compound on the electrode surface.Composite coatings of Ni-Co-LaNi5, prepared by electrolytic codepositon of Ni-Co alloys and LaNi5 particles from a sulfamate electrolyte were investigated in view of its possible application as electrocatalytic materials for the hydrogen evolution reaction(HER). The surface morphology and microstructure of Ni-Co-LaNi5 coatings were observed by means of SEM and XRD. Electrocatalytic efficiency was evaluated on the basis of electrochemical steady-state Tafel polarization and electrochemical impedance spectroscopy technology in 1mol . L-1 NaOH solution. The results were compared with Ni-Co and Ni electrodes. The real electrochemical area was estimated by apparent double-layer capacitances to account for the large difference in roughness factor of the three surfaces. The values obtained for the apparent energy of activation were 32. 48kJ . mol(-1), 46. 29kJ . mol(-1) and 57. 03kJ . mol(-1) for the HER on the Ni-Co-LaNi5, Ni-Co and Ni electrodes, respectively. The composite coatings Ni-Co-LaNi5 is catalytically more active than Ni and Ni-Co electrodes due to the increase in its real surface areas and the decrease in the apparent energy of activation caused by electrocatalytic synergistic effect of the Ni-Co alloy and the rare-earth compound on the electrode surface.

关 键 词：Ni-Co-LaNi5 复合电极材料 碱性介质 电催化 析氢性能 复合电沉积 电化学 

分 类 号：TM2[一般工业技术—材料科学与工程] O646[电气工程—电工理论与新技术]