SnO2/GDE阴极的制备及电催化还原CO2产甲酸性能  

Preparation of SnO2/GDE Cathodes and Their Electrocatalytic Reduction of CO2 to Produce Formic Acid

作　　者：卓孟宁 李飞 蒋浩[3] 陈倩文 李鹏[3] 王立章[1] ZHUO Mengning;LI Fei;JIANG Hao;CHEN Qianwen;LI Peng;WANG Lizhang(School of Environment Science and Spatial Informatics,China University of Mining and Technology,Xuzhou 221116,China;Suzhou Hongyu Environmental Technology Co.,Ltd.,Suzhou 215000,China;School of Water Resources and Environmental Engineering,East China University of Technology,Nanchang 330013,China)

机构地区：[1]中国矿业大学环境与测绘学院,徐州221116 [2]苏州市宏宇环境科技股份有限公司,苏州215000 [3]东华理工大学水资源与环境工程学院,南昌330013

出　　处：《高等学校化学学报》2020年第3期530-537,共8页Chemical Journal of Chinese Universities

基　　金：江苏省重点研发计划项目(批准号:BE2017640)资助~~

摘　　要：采用低温水热合成法制备了碳纸基底的SnO2气体扩散电极(SnO2/GDE),并对其物化特性与催化还原CO2产甲酸性能进行了研究.扫描电子显微镜、X射线衍射及X射线光电子能谱表征结果表明,在60,75,100℃下制备的催化剂均为分散性良好的纳米SnO2粉体,其粒径分别为7.9,11.8和12.9 nm.循环伏安、线性扫描伏安和电化学交流阻抗测试结果显示电极均具有优异的电催化活性,其电化学活性表面积分别为150,470,240 cm^2,通过等效电路拟合后电阻分别为8.5,3.9,6.6Ω·cm^2.在-1.8 V(vs.SCE)电位下电解,通入电量500 C时,电极都具有较高电催化还原CO2产甲酸性能,而75℃下制备的电极性能最佳,产甲酸电流密度为22.8 mA/cm^2,产甲酸法拉第效率高达93.5%;该电极经过20 h长时间电解后,产甲酸电流密度可维持在12.8 mA/cm^2,产甲酸法拉第效率稳定在约65%.The SnO2 gas diffusion electrodes(SnO2/GDE)were prepared by low temperature hydrothermal synthesis.Their physicochemical properties and catalytic performance for reduction of CO2 to produce formic acid were studied.The results of scanning electron microscopy,X-ray diffraction and X-ray photoelectron spectroscopy showed that the catalysts prepared at 60,75 and 100℃were all nano-SnO2 powder with good dispersibility,and the particle sizes were 7.9,11.8 and 12.9 nm,respectively.Cyclic voltammetry,linear sweep voltammetry and electrochemical impedance spectroscopy results showed that the electrodes had excellent electrocatalytic activity,and their electrochemically active surface area was 150,470,240 cm^2,respectively,the resistance after fitting was 8.5,3.9,and 6.6Ω·cm^2,respectively.With electrical charge of 500 C passed at applied potential of-1.8 V(vs.SCE),,the electrodes showed higher electrocatalytic performance for reduction of CO2 to produce formic acid.For the best electrode that prepared at 75℃,the current density of formic acid production was 22.8 mA/cm^2,and the Faraday efficiency of formic acid production was as high as 93.5%;after 20 h of electrolysis of this electrode,the current density of formic acid production could be maintained at 12.8 mA/cm^2,and the Faraday efficiency of formic acid production was stable at about 65%,indicating that the preparation of SnO2 catalysts by low-temperature hydrothermal synthesis has great competitiveness.

关 键 词：二氧化碳 电催化还原 低温水热合成 氧化锡气体扩散电极 

分 类 号：O646[理学—物理化学]