Insights into the effect of Ni doping on In2S3 for enhanced activity and selectivity of photocatalytic CO2 reduction
Biao Guo, Liyuan Liu, Li Ai, Xinlin Li, Yue Chang, Zhengbo Jiao, Minmin Han
Abstract
The limited photocatalytic CO 2 reduction performance mainly lies in the low utilization of photogenerated electrons during the reaction. In this work, we developed the defect level within the Ni-doped In 2 S 3 nanotube photocatalysts via a simple solvothermal method to increase the available amount of photogenerated electrons for enhanced photocatalytic CO 2 reduction performance than the pristine In 2 S 3 . The introduction of Ni element into the lattice of In 2 S 3 could significantly improve the photocatalytic activity and selectivity without destruction of the nanotube structure of In 2 S 3 . The yield of CO reaches 243.2 μmol/g/h under visible light , which is the highest reported value among In 2 S 3 photocatalysts, and is 8.2 times more than the pure In 2 S 3 . Moreover, by modulating the doping amount of Ni element, the selectivity of CO varied from 27.7% to 51.0%. Further characterizations suggest that the doping of Ni element altered the electronic bandgap arrangement of In 2 S 3 , where the position of the conduction band is conducive to the activation of CO 2 molecules. Moreover, the defect level resulting from Ni-doping not only facilitates the separation of photoexcited electron-hole pairs but also suppresses the recombination of electrons and holes. This study provides an available and reliable strategy for enhancing the photocatalytic CO 2 reduction performance of related sulfide photocatalytic materials in future studies.