Cu₂O as an emerging semiconductor in photocatalytic and photoelectrocatalytic treatment of water contaminated with organic substances: A review

A wide range of semiconductor photocatalysts have been used over the years in water treatment to eliminate toxic organic substances from wastewater. The quest for visible or solar light driven photocatalysts with striking merits such as wide range of applications, ease of preparation, tailored architecture that gives rise to improved performance, ability of dual existence as both p type or n type semiconductor, among others, presents copper(i) oxide as a promising photocatalyst. This paper reviews the recent applications of Cu2O in photocatalytic and photoelectrocatalytic treatment of water laden with organic pollutants such as dyes and pharmaceuticals. It covers the various modes of synthesis, morphologies and composites or heterostructures of Cu2O as found in the literature. Concluding remarks and future perspectives on the application of Cu2O are presented.