Rational Fabrication of MoS2/g‐C3N4 Heterostructures for Efficient Photocatalytic Degradation of Rhodamine B

• Published in: ChemistrySelect (Weinheim) Vol. 9; no. 30
• Main Authors: Zhang, Kai, Yuan, Hu, Xu, Feng, Xue, Qian, Zeng, Yi, Qi, Xuede, Li, Kun, Li, Qingwu, Zhang, Mingjie, Hu, Xuebu, Lu, Shun, Jiang, Jinxia, Qi, Xueqiang
• Format: Journal Article
• Language: English
• Published: 12-08-2024
• Subjects: MoS2/g-C3N4 heterostructure; Photocatalytic degradation; Rhodamine B; Synthetic approach
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202401034

Molybdenum disulfide (MoS2) and graphitic carbon nitride (g‐C3N4) heterojunctions were prepared through the hydrothermal method and the calcination method (namely, MoS2/g‐C3N4‐1 and MoS2/g‐C3N4‐2) for the photocatalytic degradation of Rhodamine B. X‐ray diffraction and scanning electron microscopy confirmed the formation of a heterostructure composite between MoS2 and g‐C3N4. The bandgap of MoS2 and g‐C3N4 was studied with ultraviolet–visible diffuse reflection spectroscopy and electrochemical Mott‐Schottky tests. MoS2/g‐C3N4‐1 exhibits remarkable efficiency in degrading Rhodamine B, achieving 91.2 % degradation in 1 h, which is 1.06 times higher than MoS2/g‐C3N4‐2. Additionally, the MoS2/g‐C3N4‐1 heterojunction demonstrates good reusability, maintaining a degradation efficiency of 71.2 % after 5 cycles. The reason lies in that the MoS2/g‐C3N4‐1 possesses a larger specific surface area (33.078 m2g−1) than MoS2/g‐C3N4‐2 (28.621 m2g−1). Free radical quenching experiments indicate that ⋅O2− serves as the primary active species for photocatalytic degradation. The findings indicate that incorporating g‐C3N4 into MoS2 improves its photocatalytic capability due to aligned energy bands, promoting charge transfer, and reducing electron‐hole recombination.
MoS2/g‐C3N4 heterojunctions perform enhanced photocatalytic activity compared to individual MoS2 and g‐C3N4 due to the promotion of efficient migration and separation of photogenerated electron and hole in the Z‐type heterostructure. Free radical quenching experiments indicate that ⋅O2− serves as the primary active species for the photocatalytic RhB degradation.