A Reusable Rgo/BiVO 4 Photocatalyst for Hydrogen Peroxide Synthesis in Different Flow Systems

The photocatalytic H 2 O 2 production is a sustainable and eco-friendly process, requiring mostly water, oxygen, and sunlight. In previous study, bismuth vanadate (BiVO 4 ), a semiconductor with a low band gap energy (~2.4 eV) was encapsulated with reduced graphene oxide (rGO) to promote the separation and transport of charges, preventing the recombination of photogenerated electron-hole pairs in BiVO 4 . 1% GO loading on BiVO 4 was found to deliver effective H 2 O 2 synthesis. H 2 O 2 shows stability in acidic pH (~3), hence the effectiveness of the rGO/BiVO 4 was tested under different types of acids. The order of efficiency of the acids is as follows: oxalic acid > phosphoric acid > formic acid > perchloric acid. This study involves the stability and reusability aspects of rGO/BiVO 4 exhibiting significant H 2 O 2 synthesis in the presence of oxalic acid catalyzing two-electron O 2 reduction reaction. The photocatalytic H 2 O 2 synthesis reaction following a zero-order kinetics, while the photocatalytic H 2 O 2 decomposition following a first-order kinetics has been proposed as a mechanistic insight. A photocatalytic flow reactor study has also been evaluated to assess the feasibility of H 2 O 2 generation in different reactor systems. Photocatalytic performance of rGO/BiVO 4 composite was analysed in batch as well as flow reactor conditions.