A comparative study on recent progress in efficient ZnO based nanocomposite and heterojunction photocatalysts: A review

ZnO based binary and multiple heterojunction/nanocomposite photocatalysts get profound attentions due to its solving the world crises of energy supply and utilizing sun power potential to generate H2, coal oil materials and degradation of various pollutants. In the past decade, a number of motivating fulfillments have been done on the ZnO based heterojunction/nanocomposite photocatalysts, which are significant materials for the photocatalytic process. However, the proficiency of the photocatalysis stands low because of the swift electron-hole reincorporation and low light usage. So, to solve these issues huge efforts have been made considered. Specially, the produced high quality ZnO based heterojunction/nanocomposite photocatalysts are exhibited in order to have higher photocatalytic action due to the spatial dissociation of photo-induced electron-hole couples. The aim here is to clarify increment process of the photocatalytic activity of the ZnO based binary and multiple heterojunction/nanocomposite photocatalysts, and also methodically outlines recent efficient developments related to the sketch and production of ZnO based heterojunction/nanocomposite photocatalysts. They are very encouraging for a number of variety supplications in UV–Vis light photocatalytic area, regarding with photocatalytic hydrogen generation, CO2 depletion, environmental restitution, and organic photosynthesis. Particularly, attentions have given to the fundamental principles of the various proficient ZnO based heterojunction/nanocomposite photocatalysts and recent efforts about the improvement of ZnO based heterojunction/nanocomposite photocatalysts for variety photo-degradation supplications. Furthermore, it is also provided that a brief summary and perspective on the improvements and as well as next directions in the field of ZnO based heterojunction/nanocomposite photo-catalysts. Finally, the recent researches about the ZnO based binary and multiple heterojunction/nanocomposite photocatalysts are compared in terms of their photocatalytic performance. and Amongst all, the hydrothermally produced ZnO/CuO p-n heterojunction has shown the highest photocatalyst performance of 92.62% in 5 min.