二元析氧催化剂Co_xCr_(1-x)O_(3/2)的制备及性能研究  

Preparation and Properties of Binary Oxides Co_xCr_(1-x)O_(3/2) Electrocatalysts for Oxygen Evolution Reaction

作　　者：杨太来 董文燕[1] 杨慧敏[1] 张力[1] 梁镇海[1] 

机构地区：[1]太原理工大学化学化工学院,山西太原030024

出　　处：《电化学》2015年第2期187-192,共6页Journal of Electrochemistry

基　　金：国家自然科学基金委员会与神华集团有限责任公司联合项目(No.U1261103)资助

摘　　要：用热分解法制得不同混合比例的二元金属氧化物催化剂CoxCr1-xO3/2(x=0,0.2,0.4,0.6,0.8,1),使用SEM、XRD和XPS观察表征催化剂形貌、晶型和价态,使用线性扫描伏安、阶梯波伏安和恒电位测试电极活性、过电位和稳定性.结果表明,该Co3O4和绿铬矿型Cr2O3混合物形成固溶体CoxCr1-xO3/2.x=0.2时,Co0.2Cr0.8O3/2电极性能较单一Co3O4和Cr2O3电极好,在高电位(1.0 V vs.Ag/Ag Cl),其电流强度是Co3O4的15.2倍,Cr2O3的3.75倍,其过电位(η=0.0703 V)也较Co3O4(η=0.6109 V)和Cr2O3(η=0.435 V)小,催化性能最好,在强碱性溶液(p H=13)中有良好的稳定性.Binary metal mixed oxides of Co and Cr with nominal compositional formulas, Cox Cr1-x O3/2（x = 0, 0.2, 0.4, 0.6, 0.8 and1.0）, were obtained by thermal decomposition method. The morphologies, crystal forms and valence states of the catalyst powders were analyzed by SEM, XRD and XPS, respectively. And the electrochemical properties, overpotentials and stabilities of CoxCr1-xO3/2electrodes for oxygen evolution reaction（OER） in an alkaline solution were evaluated by linear sweep voltammetry（LSV）, staircase voltammetry and chronoamperometry, respectively. The results indicated that the mixtures of Co3O4 and eskolaite-Cr2O3 formed solid solutions of CoxCr1-xO3/2. When x = 0.2, the electrocatalytic performance of Co0.2Cr0.8O3/2catalyst was better than those of Co3O4 and Cr2O3. At high potential region（1.0 V vs. Ag/Ag Cl）, the current density of Co0.2Cr0.8O3/2catalyst was 15.2 times higher than that of Co3O4 and 3.75 times higher than that of Cr2O3. Furthermore, the overpotential of Co0.2Cr0.8O3/2catalyst（η = 0.0703 V at a current density of 1×10-3A·cm-2） was much lower than those of Co3O4（η = 0.6109 V） and Cr2O3（η = 0.4350 V）, showing the best electrocatalytic property. In addition, the Co0.2Cr0.8O3/2catalyst had good stability in strong alkaline solution（p H = 13） during OER process.

关 键 词：热分解 二元氧化物 析氧反应 电化学性能 

分 类 号：O643.36[理学—物理化学]