Synthesis, Structural Property, Photophysical Property, Photocatalytic Property of Novel ZnBiErO4 under Visible Light Irradiation

A novel photocatalyst ZnBiErO₄ was firstly synthesized by solid-state reaction method and its structural and photocatalytic properties were analyzed by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance. The results demonstrated that ZnBiErO₄ crystallized with tetragonal crystal structure with space group I41/A. The lattice parameters for ZnBiErO₄ were proved to be a = b = 10.255738 Å and c = 9.938888 Å. The band gap of ZnBiErO₄ was estimated to be about 1.69 eV. Compared with nitrogen doped TiO₂, ZnBiErO₄ showed excellent photocatalytic activities for degrading methyl blue during visible light irradiation. The photocatalytic degradation of methyl blue with ZnBiErO₄ or N-doped TiO₂ as catalyst followed the first-order reaction kinetics. Moreover, the apparent first-order rate constant of ZnBiErO₄ or N-doped TiO₂ was 0.01607 min-1 or 0.00435 min-1. The reduction of total organic carbon, formation of inorganic products, such as SO₄2- and NO₃- and the evolution of CO₂ revealed the continuous mineralization of methyl blue during the photocatalytic process. ZnBiErO₄ photocatalyst had great potential to purify textile industry wastewater.