A review on modification of ZnO for highly photoactive catalyst in sustainable energy production processes

Zinc oxide (ZnO) has long been considered a great potential candidate in a variety of applications in photocatalysis. However, zinc oxide poses various drawbacks such as fast recombination of photogenerated charges and inability to catalyze under visible light excitation, which hinders further applications, therefore, modifications are highly required to tackle such. This review aims to shed light onto the basic and the influences of the modification routes namely on the photocatalytic activity of the treated zinc oxide materials. The methods of elemental doping and heterojunction construction are covered, including type, methodology, and comparative effects. Moreover, the current advances in the photo-activity of ZnO and its derivatives are also reported to provide an overview of the potential applications of zinc oxide-based materials. Aspects discussed including hydrogen production, organic photocatalysis, and energy generation. In addition, the review also briefly discusses the mechanism behind such aspects. Recently published results are provided and compared to reveal the applicability of ZnO on a real-life scale as the photocatalyst. In the end, future perspectives are provided for the aid in future study of photocatalysis as well as its potent application.