Photoelectrooxidation of ethanol on a lanthanum cobalt oxide/platinum modified FTO electrode

In recent years, direct ethanol fuel cells (DEFCs) have gradually attracted more interest as an alternative power source [1]. Ethanol is a promising fuel because it can be produced easily from abundant biomass, and it has lower toxicity than methanol [2]. In addition, the high theoretical mass-energy density of ethanol (~8.0 Wh g-1) is appropriate for the rising demand for future energy [3]. Platinum is most commonly used as an anode material in DEFCs. Although ethanol electrooxidation on Pt electrodes has been widely investigated, some critical problems still exist when only pure Pt electrodes are used [4]. In the present study, a new photoelectrocatalyst composed of lanthanum cobalt oxide (LaCoO3) was prepared for electrooxidation of ethanol. The photoelectrocatalyst was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The surface of the fluorine doped tin oxide (FTO) electrode was modified with LaCoO3 photoelectrocatalyst using drop casting method and then Pt nanoparticles through electrochemical deposition. Cyclic voltammetry, chronoamperometry, scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) were used to investigate the surface of the modified electrode.The effect of several parameters such as ethanol concentration, amount of the Pt nanoparticles and LaCoO3 photoelectrocatalyst controlling the electrooxidation of ethanol were examined and optimized. The results obtained in this study, indicate that the proposed electrode possess a high electrocatalytic activity for ethanol electrooxidation.