Synthesis of bismuth vanadate: its application in H2 evolution and sunlight-driven photodegradation

Abstract

A nanocrystalline m-BiVO₄ photocatalyst for H₂ evolution, which works under UV-light irradiation, has been synthesized by a facile solution combustion synthesis method. Hydrogen evolution over BiVO₄ is a significant result in the field of renewable energy sources and here we are the first to show hydrogen evolution experimentally with BiVO₄ in the absence of either coupling oxides or doping metals. The yield of hydrogen generated is about 489 μmol per 2.5 h of reaction under UV irradiation. The ultra-light yellow crystalline combustion derived nanopowder exhibits porous morphology with a strong absorption in the visible light region. The estimated band gap of BiVO₄ powder is about 2.52 eV. The powder shows highly visible photocatalytic activity towards methylene blue degradation under sun light irradiation. The H₂ evolution and photocatalytic activity of BiVO₄ nanocrystalline powder can be attributed to its physical properties such as nanosize particles and large surface area.