Bismuth vanadate in photoelectrocatalytic water treatment systems for the degradation of organics: A review on recent trends

Abstract

Photoelectrocatalytic degradation, an advanced oxidation process, which combines both light and electrical energy for chemical reaction has proven to be an efficient method for the degradation of organics in wastewater. The efficiency of photoelectrocatalytic degradation depends greatly on the choice of material for photoanode. Bismuth vanadate (BiVO 4 ) has been identified as a suitable electrode material and it has been widely applied in visible light mediated photocatalysis, photoelectrochemical water splitting and photoelectrocatalytic water treatment applications. These applications are due to its attractive properties such as narrow band gap, low toxicity and excellent physicochemical stability. In the past, much focus has been on photocatalysis and photoelectrochemical water splitting applications of BiVO 4 . However, due to the recent interest in the application of BiVO 4 in photoelectrocatalysis for wastewater treatment applications, there is a need to present to the electrochemistry community (and other related science and engineering communities on water and materials), a review on the recent applications of BiVO 4 based photoanodes for the photoelectrocatalytic degradation of recalcitrant organic pollutants in wastewater. Additionally, brief insights into the synthesis and strategies of improving the efficiency of BiVO 4 are presented. This review provides relevant information that will be beneficial for future works on the use of BiVO 4 for water treatment applications. • Recent applications of BiVO 4 in PEC water treatment of organics are reviewed. • Methods of enhancing photoelectrochemical efficiency of BiVO 4 anodes are discussed. • Mechanisms of PEC degradation of organics at BiVO 4 photoanodes are highlighted. • PEC degradation of organics on couples systems with PEC fuel cells are discussed.