棒状多孔NiCo_2O_4粉末的可控制备及其电催化性能研究  

Controlled Synthesis and Electrocatalytic Performance of Porous Nickel Cobaltite Rods

作　　者：湛菁[1] 陆二聚 蔡梦[1] 马雅琳[1] 张传福[1] 

机构地区：[1]中南大学冶金与环境学院,长沙410083

出　　处：《无机材料学报》2017年第1期11-17,共7页Journal of Inorganic Materials

基　　金：国家自然科学基金青年基金(51404306);湖南省科学技术厅科技计划(2010FJ3012);高等学校博士学科点专项科研基金(20090162120080)~~

摘　　要：以NiCl_2·6H_2O,CoCl_2·6H_2O和草酸为原料,利用氨水为配位剂和溶液pH调节剂,通过配位共沉淀–热分解法制备了棒状多孔NiCo_2O_4粉末,采用X射线衍射、扫描电镜、透射电镜以及比表面积仪对前驱体和NiCo_2O_4粉末的形貌和结构进行了表征,考察了溶液pH对前驱体粉末形貌和分散性的影响;采用循环伏安法和计时电流法研究了乙醇在棒状多孔NiCo_2O_4粉末修饰的玻碳电极上的电催化性能。结果表明:前驱体的形貌与溶液的pH有关,热分解得到的NiCo_2O_4粉末继承了前驱体形貌,呈多孔棒状,比表面积为89 m^2/g,平均孔径为12.56 nm。该粉末对乙醇具有良好的电催化活性,氧化峰电流与乙醇浓度、扫速的平方根均呈直线关系,表明棒状多孔NiCo_2O_4粉末对乙醇的催化反应机理为扩散控制。Porous rod-like NiCo2O4 powders were synthesized by coordination precipitation-thermal decomposition using NiCl2·6H2O, COCl2·6H2O and oxalate as starting materials, and ammonia as coordination agent and pH adjustor. Morphology and structure of the precursor and as-prepared porous NiCo2O4 rods were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, and N2 adsorption/desorption analysis. Influence of solution pH on the morphology of the precurosr was investigated. Cyclic voltammetry and chronoamperometry were applied to investigate the electrochemical oxidation of ethanol on porous NiCo2O4 rods modified glassy carbon electrode in alkaline medium. The results show that morphology of the precursor depends on pH of the solution. The as-prepared NiCo2O4 rod inherits the morphology of the precursor and shows porous structures consisting of mesopores with a significantly high specific surface area of 89 m2/g and average pore diameter of 12.56 nm. Porous rod-like NiCo2O4powders exhibit high electrocatalytic activity in cyclic voltammetry measurement. The linear relationships between oxidation peak current and ethanol concentration, and square root of scan rate indicate that ethanol diffusion is a rate-determining step in its oxidation on as-prepared porous NiCo204 rods.

关 键 词：直接乙醇燃料电池 电催化 乙醇氧化 NiCo2O4 配位共沉淀 

分 类 号：O614[理学—无机化学]