Advances in designing heterojunction photocatalytic materials

Under the background of increasing energy crisis and global warming, semiconductor-based photocatalysis has received tremendous attention due to its potential application in green energy production, CO2 reduction and pollutant degradation. The photocatalytic activity of semiconductors, however, remains low due to issues like fast recombination of photo-generated electron-hole pairs, limited electron mobility, restricted optical absorption or insufficient active sites. Designing appropriate heterojunctions is proved to be a promising method to address most of these issues and thus to improve the photocatalytic performance. In this review, the working mechanism of various heterojunctions is presented systematically. The most recent advances of strategies in designing and preparing efficient heterojunction photocatalysts are further summarized and some perspectives on the future directions in this field are provided.