Electrocatalytic properties of Pt-Bi electrodes towards the electrooxidation of formic acid

Journal of the Serbian Chemical Society

关键词: formic acid;    electrochemical oxidation;    Pt2Bi catalyst;    Pt/Biirr catalyst;    fuel cell;   

DOI  :  10.2298/JSC121012138L

来源: DOAJ

【 摘 要 】

Formic acid oxidation was studied on two Pt-Bi catalysts, Pt2Bi andpolycrystalline Pt modified by irreversible adsorbed Bi (Pt/Biirr) in orderto establish the difference between the effects of Biirr and Bi in alloyedstate. The results were compared to pure Pt. It was found that bothbimetallic catalysts were more active than Pt with the onset potentialsshifted to more negative values and the currents at 0.0 V vs. SCE (understeady state conditions) improved up to two order of magnitude. The origin ofPt2Bi high activity and stability is increased selectivity toward formic aciddehydrogenation caused by the ensemble and electronic effect and suppressionof Bi leaching from the surface during formic acid oxidation. However,although Pt/Biirr also shows remarkable initial activity compared to pure Pt,dissolution of Bi is not suppressed and the poisoning of the electrodesurface induced by dehydration path is observed. Comparison of the initialquasi-steady state and potentiodynamic results obtained for these two Pt-Bicatalysts revealed that the electronic effect, existing only in the alloy,contributes earlier start of the reaction, while the maximum current densityis determined by the ensemble effect. [Projekat Ministarstva nauke RepublikeSrbije, br. H-172060]

【 授权许可】

Unknown