Enhanced photocatalytic reduction of CO2 over pg-C3N4-supported TiO2 nanoparticles with Ag modification.

Photoreduction of CO 2 has been a promising route to decrease CO 2 emission and obtain valuable fuels or chemical raw materials, but it still faces tremendous challenge. Composite catalyst fabricated with TiO 2 and g-C 3 N 4 might exhibit great competitive advantages, due to their potential application prospects in the field of photocatalysis. Herein, we prepared a novel pg-C 3 N 4 /Ag-TiO 2 composite catalyst by using the porous defective g-C 3 N 4 (pg-C 3 N 4) and Ag doped TiO 2 , and a three-component S-scheme heterojunction had been built. Compared to individual g-C 3 N 4 or Ag-TiO 2 , the synthesized pg-C 3 N 4 /Ag-TiO 2 material demonstrates significantly increased photocatalytic activity for the reduction of CO 2 and the AQE reaches 2.364%. In addition to improved charge separation efficiency of S-scheme heterojunctions, increased surface area of the catalyst could also be responsible for the enhanced photocatalytic performance. Experimental and computational reveals that when Ag is added to TiO 2 , its work function is adjusted, and electrons are transferred in a different direction, promoting the formation of S-scheme heterojunctions. [Display omitted] [ABSTRACT FROM AUTHOR]