PtRu/C表面甲醇电催化氧化动力学的非线性谱学分析  

Nonlinear Spectroscopy Analysis for Electrocatalytic Oxidation of Methanol on PtRu/C Surface

作　　者：石越[1] 毛庆[1] 肖成 景维云 张学元 SHI Yue;MAO Qing;XIAO Cheng;JING Weiyun;ZHANG Xueyuan(School of Chemical Engineering,Dalian University of Technology,Dalian 116023,China;GAMRY Instruments,Warminster,PA 18974,America)

机构地区：[1]大连理工大学化工学院,大连116023 [2]GAMRY Instruments,Warminster,PA 18974,America

出　　处：《高等学校化学学报》2018年第9期2017-2024,共8页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21403029),辽宁省自然科学基金(批准号:201602162)和中国科学院燃料电池及复合电能源重点实验室开放课题(批准号:KLFC201612)资助.

摘　　要：应用新一代电化学谱学分析方法——总谐波失真(THD)谱考察了PtRu/C表面甲醇电催化氧化的非线性频响行为,并通过对比Ru含量不同的催化剂表面甲醇氧化THD谱的实验表征与数值模拟结果,探讨了其在甲醇电催化氧化机理识别以及电极性能诊断中应用的可行性.THD谱的实验结果表明,在0.25~1 Hz频率范围内,THD谱强度随Ru含量的降低而增加,随甲醇浓度损失的降低而降低.相反的变化趋势使THD相比于电化学阻抗谱(EIS)在这2种失效的诊断中优势更加明显.THD谱的数值模拟结果表明,在中间产物氧化电势相关性与反应物等温吸附模式不同的机理比较中,基于Kauranen-Frumkin/Temkin机理的甲醇氧化动力学可以再现不同Ru含量的PtRu/C表面甲醇电催化氧化的线性与非线性频率响应结果.A new generation of electrochemical spectroscopic analysis--total harmonic distortion(THD)spectrum was used to characterize the nonlinear characteristic frequency response of methanol electrocatalytic oxidation on PtRu/C surface.By comparing the experimental and numerical results of THD spectra of methanol oxidation on Ru catalysts with different contents,this work have qualitatively investigated the feasibility of THD spectrum in methanol electrocatalytic oxidation mechanism identification and electrode performance diagnosis.The experimental results show that in the range of 0.25-1 Hz frequency domain,THD increases with the decrease of Ru content,and decreases with the decrease of methanol concentration.Compared to EIS,THD has advantages over this failure diagnosis due to its opposite tendency of experimental results.The results of numerical simulation of THD spectrum show that according to whether electrode-potential-related step exist in the oxidation of CO ads and different isothermal adsorption models,the mechanism of methanol oxidation based on Kauranen-Frumkin/Temkin mechanism can reproduce steady state,linear and nonlinear frequency response of methanol electrocatalytic oxidation with different Ru content on PtRu/C surface.

关 键 词：总谐波失真谱 直接甲醇燃料电池 非线性频率响应 钉流失诊断 

分 类 号：O646[理学—物理化学]