Abstract

The BiVO₄ microspheres and Sm³⁺-doped BiVO₄ polygons were prepared via a facile hydrothermal method by means of K₆V₁₀O₂₈·9H₂O as a novel vanadium source. Optimized temperature and pH value of prepared BiVO₄ were obtained. The polycrystalline BiVO₄ microspheres prepared at T = 140 °C, pH 4, demonstrates the best photocatalytic activities for degrading dyes under UV radiation. This is resulted due to transfers of photogenerated electrons from tetragonal to monoclinic phases. In contrast to the undoped BiVO₄, the photocatalytic activity of Sm³⁺-doped BiVO₄ polygons is drastically enhanced not only under UV radiation but also under visible light radiation. The optimized Sm content was found to be 10 %. Enhanced efficiency with the doped sample is attributed to the dopants’ role in blocking recombination of photogenerated electron–hole pairs. This work offers a simple route to obtain mixed phase BiVO₄ and provide an effective way to achieve higher photocatalytic activity by doping the Sm³⁺ in the semiconductor catalysts.