复合电沉积制备Ni/NiFe_2O_4电极及其电催化析氧性能  

Ni/NiFe_2O_4 Composite Electrode Prepared by Electro-deposition and Its Electro-catalytic Performance Towards Oxygen Evolution Reaction

作　　者：王丽品[1] 王森林[1] 段钱花[1] 

机构地区：[1]华侨大学材料科学与工程学院应用化学系,厦门361021

出　　处：《应用化学》2013年第6期690-697,共8页Chinese Journal of Applied Chemistry

摘　　要：采用共沉淀法制备尖晶石型NiFe2O4粉体,然后将其加入瓦特镀镍液中,采用复合电沉积制备Ni/NiFe2O4复合电极。通过改变镀液的pH值、阴极电流密度jk等条件,探索最佳工艺条件。运用扫描电子显微镜(SEM)、能谱分析(EDS)和X射线衍射仪(XRD)表征粉体以及复合电极的组成和结构。结果表明,在镀液pH值为5.8～6.0、jk为40×10-3～60×10-3A/cm2条件下,所得复合电极中NiFe2O4的质量分数最高可达55.15%。采用循环伏安、稳态极化以及恒电势阶跃,研究了电极在5 mol/L KOH溶液中的电催化析氧性能。与Ni电极对比,Ni/NiFe2O4复合电极的电催化析氧性能更好,比表面积是镍电极的23.02倍,表观活化能降低了62.07 kJ/mol。恒电势长时间电解析氧实验表明,Ni/NiFe2O4复合电极在碱性介质中具有较高的析氧稳定性。The spinel-type NiFe2O4 powders have been synthesized by a hydroxide co-precipitation method. The Ni/NiFe2O4 composite coating was prepared through electro-deposition in Watt nickel plating by adding some NiFe2O4 powders. The optimized plating conditions for the composite electro-deposition were investigated by varying parameters, such as the plating solution pH and the cathode current density jk. The composition and structure of the Ni/NiFe2O4 composite coating were characterized by scanning electron microscopy（SEM）, energy X-ray diffraction（XRD） and dispersive spectrometer（EDS）. The results show that the NiFe2O4 mass content in the Ni/NiFe2O4 composite coating is the highest（55.15%） at optimized plating conditions of a solution pH=5.8～6.0 and a cathodic current density jk=40×10-3～60×10-3 A/cm2. In 5 mol/L KOH solution, the electro-catalytic properties towards the oxygen evolution reaction（OER） of the Ni/NiFe2O4 composite electrode was studied using cyclic voltammetry, steady-state polarization, and chronoamperometry. Compared with the nickel electrode, the electro-catalytic properties towards OER of the Ni/NiFe2O4 electrode is higher and the apparent activation energy is decreased by 62.07 kJ/mol, and its specific surface area is 23.02 times as large as that of the nickel electrode. The constant-potential electrolysis with long time for OER shows that the stability of the Ni/NiFe2O4 composite electrode is good.

关 键 词：复合电沉积 NI NIFE2O4 析氧反应 电催化 

分 类 号：O646[理学—物理化学]