Transition metal phosphides for heterogeneous Fenton-like oxidation of contaminants in water

Abstract

• Transition metal phosphides (MPs) are attractive heterogeneous Fenton-like catalysts. • Metalloid structure and superior conductivity of MPs favor interfacial catalysis. • Metal redox cycling are accelerated by electron supply from reductive phosphide. • Electron- and photo-Fenton processes assist Fenton-like oxidation of pollutants. The development of low cost, efficient materials for heterogeneous Fenton-like catalysis continues to be an active area of research for water treatment. Over the past few years, transition metal phosphides (MPs) have witnessed rapid development and their application fields are rapidly expanding from photocatalytic water splitting to advanced oxidation. The unique metalloid structure and superior electron conductivity of these materials endow them with significantly raised catalytic activity for interfacial reactions relative to their corresponding oxyhydroxides, although the existing studies are still at laboratory scale and the insufficient mechanical study and material engineering are still key barriers to practical application. In this review, we summarize the progress in MPs-based heterogenous Fenton-like processes by introducing the fundamentals and catalytic performances of various MPs for activation of hydrogen peroxide, persulfate or dioxygen, both under normal and electro-assisted or photo-assisted scenarios. In addition, we discuss the remaining challenges for their practical water treatment application and offer perspectives on possible future research directions.