A review on monoclinic metal molybdate photocatalyst for environmental remediation

Abstract

Utilization of solar energy by photocatalysts is a promising green technology for the degradation of organic pollutants in wastewater. Among the various types of metal molybdate photocatalysts applied for environmental remediation, those with monoclinic structures (NiMoO4, CoMoO4, MnMoO4, ZnMoO4, Ce2(MoO4)3, Fe2(MoO4)3, and Bi2MoO6) constitute the largest group of them. These materials possess many valuable properties such as tunable band structures, environmental friendliness, low cost, large surface areas, and tunable electrical conductivity. These promising materials have evidenced effective removal capability for organic pollutants in wastewater. This review focuses on semiconducting metal molybdates containing a monoclinic structure, with an emphasis on various modification strategies employing morphology control, doping, plasmonic material fabrication, or composite fabrication to enhance the photocatalytic activities for the degradation of organic pollutants. This review also discusses the possible obstacles to environmental applications targeted at the removal of organic pollutants, as well as the key challenges, future directions, and prospects.