Enhanced photocatalytic CO2 reduction activity using a Bi4V2O11/single-walled carbon nanotube/g-C3N4 S-scheme heterojunction.

In this paper, a Bi 4 V 2 O 11 /SWNT/g-C 3 N 4 S-scheme heterojunction photocatalyst was reasonably constructed to achieve efficient photocatalytic CO 2 reduction.This job is prospective to offer more empirical reference for the construction of higher activity g-C 3 N 4 photocatalytic materials. [Display omitted] • The ultrathin porous nanosheets have large specific surface area and more active sites. • Oxygen vacancies increase the adsorption capacity of CO 2. • SWNTs can increase the charge separation efficiency even further. • S-scheme heterostructure can increase the effectiveness of photogenerated carrier separation. • The Bi 4 V 2 O 11 /SWNT/g-C 3 N 4 S-scheme heterojunction catalyst has good photocatalytic performance. A novel Bi 4 V 2 O 11 /single-walled carbon nanotube (SWNT)/g-C 3 N 4 S-scheme heterojunction photocatalyst is prepared using an in situ solvothermal growth method. Heterostructures are constructed by coupling the defective semiconductor Bi 4 V 2 O 11 with ultrathin porous g-C 3 N 4 nanosheets. To improve the photocatalytic CO 2 reduction activity, oxygen defects are used to enhance electron capture and CO 2 adsorption, the S-scheme heterojunction is used to improve the separation efficiency of the photogenerated carriers and SWNTs are used to form high-speed electron transport channels. The experimental results indicate that the maximum CO formation rate of Bi 4 V 2 O 11 /SWNT/g-C 3 N 4 is 18.6 μmol h−1 g−1, which is 2.7 and 2.4 times that of the ultrathin porous g-C 3 N 4 nanosheets and Bi 4 V 2 O 11 heated for 15 h, respectively, and 3.4 times that of standard g-C 3 N 4. This work provides a vital reference point for the in situ construction of S-scheme heterojunctions with defects. [ABSTRACT FROM AUTHOR]