Enhancement of Electrocatalytic Oxidation of Glycerol by Plasmonics

Direct alcohol fuel cells have attracted interest as an alternative energy conversion device, but most systems use either methanol or ethanol. Glycerol, a chemical byproduct of biodiesel production, is a more desirable fuel, because it is safer and has a higher energy density. With this aim, binary Ag−Au plasmonic nanoparticles (NPs) were immobilized onto electrodes and evaluated in a glycerol fuel cell. When illuminated with visible light, the power output of the fuel cell increased 100 %. The output at varying wavelengths and light intensities indicates that the enhanced oxidation was related to the catalyst's plasmonic properties. Cyclic voltammetry (CV) showed that the surface plasmon resonance (SPR) of the catalyst did not cause heating at the electrode surface, so the enhancement must be a result of either hot electron transfer or breakdown of the fuel into simpler molecules by photogenerated reactive oxygen species. This is the first report of the photoelectrocatalytic oxidation of a complex alcohol fuel by a plasmonic material.