Oscillatory instabilities during the electrocatalytic oxidation of methanol on platinum

Journal of the Brazilian Chemical Society

Sitta, Elton¹  Batista, Bruno C.¹  Martins, Andre L.¹  Universidade de São Paulo, São Carlos, Brazil¹  Varela, Hamilton¹ 

关键词: current and potential oscillations;    methanol;    electrocatalysis;    in situ FTIR;   

DOI  :  10.1590/S0103-50532008000400011

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

It is described in this paper the experimental observation of oscillatory dynamics during the electrocatalytic oxidation of methanol on platinum. Besides the previously reported potential oscillations, current oscillations obtained under potentiostatic control are also presented. The existence region of current oscillations is mapped in an applied voltage x resistance bifurcation diagram. Conjointly with electrochemical investigations, in situ FTIR spectroscopy was also employed in the present studies. Although we were not able to follow eventual intermediate coverage changes during the oscillations, those experiments revealled that the mean coverage of adsorbed carbon monoxide remains appreciably high along the oscillations. Results are discussed and compared with the oscillations observed in the electrooxidation of formic acid, a system whose behavior is more understood and widely supported by in situ spectroscopic data.

【 授权许可】

Unknown