Comparative electrochemical analysis demonstrates altered kinetics and lower Tafel slopes for oxygen reduction in sputtered platinum films, suggesting an adsorption-controlled reaction near 0.8 V.
Tafel plots and cyclic voltammetric responses of sputtered Pt thin films are compared to those of polished bulk polycrystalline Pt in various concentrations of KOH from 0.1 to 6.0 M . Distinct differences in the CV curves between bulk and sputtered Pt are observed for the hydrogen adsorption peaks and the initial oxide formation peak. As with bulk platinum, dual slope Tafel plots for O 2 reduction were observed on the sputtered samples. Above 0.85V (region 1), the Tafel slopes of both were about 50 mV/decade. Below 0.85V (region 2) the slope depends on KOH concentration and temperature, but is lower for sputtered Pt. Results for Pt‐C thin films show a still lower slope in region 2, and no detectable hydrogen adsorption or desorption peaks on the CV response curves. The data presented here provide evidence that the change in slope near 0.8V is associated with an adsorption step in the process of O 2 reduction on the Pt surface.
No takes yet. Share an insight, caveat, or question.
Weber et al. (1986) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: