Electrooxidation of methanol using lanthanum cobalt oxide/platinum photoelectrocatalyst

Direct methanol fuel cells (DMFCs) have recently received great attention as a sustainable power source for dealing with energy shortage and environmental pollution due to their fairly high energy density, low operating temperature and very low environmental intrusion [1-3]. Pt-based electrocatalysts in DMFCs, have shown high activity for methanol electrooxidation reactions at anode of a fuell cell. However, pure Pt as anode is easily poisoned by carbon monoxide (CO) [4]. Therefore, considerable efforts have been recently focused on fabrication of easily available and high active electrocatalysts for the DMFCs. In the present work, lanthanum cobalt oxide (LaCoO3) as a photoelectrocatalyst was synthesized for electrooxidation of methanol and it was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). At first, the photoelectrocatalyst was dropped onto the surface of the fluorine doped tin oxide (FTO) electrode. Then, the surface of the electrode was potentiostatically coated with Pt nanoparticles at constant potential of - 0.2 V. The surface of the modified electrode was characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques. The electrooxidation of methanol molecules on the surface of the modified electrode was studied using cyclic voltammetry and chronoamperometry. The results show that the lanthanum cobalt oxide/platinum photoelectrocatalyst show a high electrocatalytic activity towards the methanol electrooxidation reaction as compared to Pt catalyst

Keywords:

Direct methanol fuel cells , electrooxidation , photoelectrocatalyst , fluorine doped tin oxide