摘要
用“分解极化曲线”法研究PbO_2电极上Ce^(4+)阳极形成的动力学。测得电位在1.7～1.9V(vs.SCE)区域和高于1.9V区域的O_2和Ce^(4+)的极化曲线的Tafel斜率和两者的动力学方程。推测了PbO_2电极上Ce^(4+)形成和O_2析出的机理及两区域内反应机理的差别。所推得的动力学方程均与实验相符。
The kinetic data related respectively to Ce4+ anodic formation and O2 anodic evolution at PbO2 electrode in 0. 5 mol/L H2SO4+x mol/L Ce2(SO4)3(x=0. 01-0. 10) and 0. 025 mol/L Ce2(SO4)3+x mol/L H2SO4(x=1. 09-4. 20) solutions were obtained by the method of resolving the steady-state polarization curve. Experiments show that the anodic formation of Ce4+ and O2 anodic evolution at PbO2 electrode in the mixed H2SO4-Ce2(SO4)3 solutions can be described by i(O2)=k1aw4expβ F/RT,i(Ce4+) = k2aw2[Ce3+]expβ F/2RT at the potential region 1.7-1.9 V and by i(O2) = k'1aw4exp2β F/RT, i(Ce4+) = k2aw2[Ce3+]expβ F/RT at the potential region above 1.9V (vs. SCE). On the basis of kinetics data thus obtained the mechanisms are proposed, which can be used to explain many experimental phenomena.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1995年第7期1109-1113,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金
关键词
阳极氧化
氧化动力学
铈离子
二氧化铅电极
PbO2 anode, Anodic oxidation of Ce3+ ion, Anodic formation of Ce4+ ion, Kinet-ics and mechanism
