High Performance Pt‐Os/TiO 2 /GO Photoelectrocatalyst for Methanol Oxidation in Acidic Media

Herein, we report the preparation of a new and highly efficient photoelectrocatalyst for electrocatalitic oxidation of methanol in acidic media. To this end, a fluorine‐tin oxide (FTO) electrode derived from commercial FTO plates was modified layer by layer with graphene oxide (GO) and titanium dioxide (TiO 2 ), and decorated with platinum‐osmium nanoparticles (Pt‐OsNPs) through co‐electrodeposition technique. GO nanosheets and TiO 2 nanoparticles not only served as signal amplifier and photoactive material, respectively, but also, they provided a high surface area for electrodeposition of Pt‐OsNPs. The scanning electron microscopy (SEM) images and energy dispersive X‐ray spectroscopy (EDS) spectra revealed the change of the FTO surface in each modification step. The photo electrocatalytic activity of Pt‐Os/TiO 2 /GO/FTO for methanol oxidation was assessed under visible light irradiation, and an anodic peak current density of about 10 mA cm −2 was obtained at 0.75 V. The chronoamperometry measurements showed the improved durability of Pt‐Os/TiO 2 /GO/FTO photocatalyst compared to other studied catalysts including Pt/FTO, Pt/GO/FTO, and Pt/TiO 2 /GO/FTO. The values of exchange current density ( J 0 ) obtained from Tofel plots for studied catalysts indicted that the methanol oxidation reaction is less limited kinetically in the presence of Pt‐Os/TiO 2 /GO/FTO photocatalyst.