Abstract
Shine a light: A PtNiRu/TiO~2~ anode catalyst for direct ethanol fuel cells shows photocatalytic activity. The peak current density for ethanol oxidation under solar light illumination is 2β3 times greater than that in the absence of solar light. Ethanol is oxidized by lightβgenerated holes, and the electrons are collected by the TiO~2~ support to generate the oxidation current.magnified image
Novel PtNiRu/TiO~2~ anode catalysts for direct ethanol fuel cells (DEFCs) were prepared from PtNiRu nanoparticles (1:1:1 atomic ratios) and a nanoporous TiO~2~ film by a solβgel and electrodeposition method. The performances of the catalysts for ethanol oxidation were investigated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The results indicate a remarkable enhancement of activity for ethanol oxidation under solar light illumination. Under solar light illumination, the generated oxidation peak current density is 24.6β
mAβcm^β2^, which is about 2.5 times higher than that observed without solar light (9.9β
mAβcm^β2^). The high catalytic activity of the PtNiRu/TiO~2~ complex catalyst for the electrooxidation of ethanol may be attributed to the modified metal/nanoporous TiO~2~ film, and the enhanced electrooxidation of ethanol under solar light may be due to the photogeneration of holes in the modified nanoporous TiO~2~ film.