In-situ fabrication of Bi2S3/BiVO4/Mn0.5Cd0.5S-DETA ternary S-scheme heterostructure with effective interface charge separation and CO2 reduction performance

Abstract

• Bi 2 S 3 /BiVO 4 /Mn 0.5 Cd 0.5 S-DETA ternary heterostructure is obtained. • The heterostructure exhibited excellent photocatalytic CO 2 reduction and stability. • Mechanism of charge transfer and separation in S-scheme heterojunction is proposed. • S-scheme photocatalytic mechanism is discussed. Exploring new and efficient photocatalysts to boost photocatalytic CO 2 reduction is of critical importance for solar-to-fuel conversion. In this study, through the in-situ growth method, a series of S-scheme mechanism Bi 2 S 3 /BiVO 4 /Mn 0.5 Cd 0.5 S-DETA nanocomposites with good photocatalytic activity were synthesized. The extremely small size of Mn 0.5 Cd 0.5 S-DETA nanoparticles provides more active sites for photocatalytic reactions. In order to solve the serious shortcomings of sulfide photo-corrosion, BiVO 4 were introduced as oxidation catalyst to consume too many holes and improve the stability of the material. In addition, the in-situ growth method produces the reduction cocatalyst Bi 2 S 3 during the BiVO 4 and Mn 0.5 Cd 0.5 S-DETA recombination process, thereby improving the efficiency of charge transfer at their interface contact. The ternary composite unveils a higher CO 2 -reduction rate (44.74 μmol g −1 h −1 ) comparing with pristine BiVO 4 (14.11 μmol g −1 h −1 ). The enhanced photocatalytic CO 2 reduction performance is due to the special interface structure of the S-scheme Bi 2 S 3 /BiVO 4 /Mn 0.5 Cd 0.5 S-DETA photocatalyst, which facilitates the charge separation at the interface and improves its photocatalytic activity and stability. .