A study on photoelectrochemical glycerol oxidation using BiVO4 photoanode

Abstract

This thesis focuses on the oxidation of glycerol to produce dihydroxyacetone (DHA) within a photoelectrochemical system utilizing BiVO4 as the photoanode material. Utilizing glycerol, the main by-product from biodiesel production process, is receiving much attention in research area since its industrial application potential. Also, photoelectrochemical system enables efficient reaction progress at low energy input. BiVO4 semiconductor, affordable and exhibiting small bandgap, was used as photoanode material. Through pH optimization and potential engineering, the study refines the reaction environment, revealing an optimum DHA production rate of 137.8 mmol m-2 h-1 at reaction condition of 1.0 V vs RHE, pH 2. Employing N2 treatment inducing oxygen vacancies, higher DHA productivity was obtained, achieving DHA production rate of 171.5 mmol m- 2 h-1. Comparative bulk, surface analysis and product tests between bare BiVO4 and N2-treated BiVO4 revealed that the DHA productivity was enhanced because the oxygen vacancies improved carrier density and thus bulk efficiency of BiVO4 photoanode. This thesis suggests that the photoelectrochemical glycerol oxidation reaction has the potential for industrial development.