电沉积Ni/LaNiO_3复合电极及其在碱性介质中的析氧性能  

Electrodeposition of Ni/LaNiO_3 Composite Electrode and Its Properties Toward Oxygen Evolution Reaction in Alkaline Media

作　　者：王森林[1] 鲍晋珍[1] 

机构地区：[1]华侨大学材料科学与工程学院应用化学系,福建厦门361021

出　　处：《中国稀土学报》2012年第3期350-357,共8页Journal of the Chinese Society of Rare Earths

摘　　要：采用溶胶-凝胶法制备了钙钛矿型复合氧化物LaNiO3,然后将其加入瓦特镀镍液中进行复合电沉积,研究了镀液pH值和阴极电流密度对Ni/LaNiO3复合镀层组成的影响。运用扫描电镜(SEM)、能谱分析(EDS)和X射线衍射(XRD)等对复合镀层进行表征,结果表明:最佳电沉积工艺条件是镀液pH=5.8和阴极电流密度jk=90 mA.cm-2,所得的Ni/LaNiO3复合镀层中LaNiO3的质量含量约为60%。用循环伏安、稳态极化、恒电位阶跃、电化学阻抗谱等电化学技术评价了Ni/LaNiO3复合电极的析氧性能。结果表明:在5 mol.L-1的KOH溶液中,Ni/LaNiO3复合电极的起始析氧电位较镍电极负,表观活化自由能比镍电极降低约2/3,比表面积约为镍电极的55倍,析氧电催化性能得到大幅度提高。A perovskite composite oxide LaNiO3 was obtained by sol-gel method.Then,a Ni/LaNiO3 composite coating was prepared by composite electro-deposition technique in watt solution plating Ni by mixing with LaNiO3 powders.The effect of the plating bath pH and the cathode current density on the composition of the composite coating was investigated,respectively.The surface morphology,the LaNiO3 content and the structure of a Ni/LaNiO3 composite coating were characterized by scanning electron microscopy（SEM）,energy dispersive spectrometer（EDS） and X-ray diffraction（XRD）.As a result,the LaNiO3 content of the Ni/LaNiO3 composite coating had the highest value（about 60%） at the best plating conditions,which were the bath pH of 5.8 and the cathodic current density of 90 mA · cm-2.In a 5 mol · L-1 KOH solution,the electrocatalytic properties toward the oxygen evolution reaction（OER）of the Ni/LaNiO3 composite electrode was studied using cyclic voltammetry,electrochemical steady-state polarization,chronoamperometry and electrochemical impendence spectroscopy（EIS）.Compared with a nickel electrode,the electrocatalytic properties toward OER of the Ni/LaNiO3 composite electrode improved greatly,and the apparent activation energy was reduced by 2/3,its specific surface was 55 times larger than that of a nickel electrode.

关 键 词：Ni/LaNiO3 钙钛矿 复合电沉积 析氧性能 稀土 

分 类 号：O646[理学—物理化学]