Enhanced photocatalytic degradation of glyphosate over 2D CoS/BiOBr heterojunctions under visible light irradiation

Two-dimensional (2D) heterojunction photocatalysts can shorten the carrier transfer pathway. In this study, CoS nanoparticles were deposited on the surface of 2D BiOBr nanosheets to fabricate novel ultrathin and intimate contact 2D heterojunction photocatalysts by a two-step solvothermal route. Under visible-light (lambda > 400 nm) irradiation, the apparent reaction rate constant of glyphosate degradation over 10%CoS/BiOBr reaches 0.0074 min(-1) (74.7% glyphosate was degraded within 3 h), which is about 5.3 times that of pure BiOBr (0.0014 min(-1)). The extraordinary photocatalytic performance is attributed to the strong visible-light absorption, the effective charge separation and low charge transfer resistance. The possible photocatalytic reaction process and mechanism over CoS/BiOBr heterojunctions are proposed. Moreover, the 10%CoS/BiOBr sample shows good reusability and stability. This work could provide a new insight for the design and development of 2D heterojunction photocatalysts.

Automated summary

This study developed 2D heterojunction photocatalysts with enhanced photocatalytic performance by depositing CoS nanoparticles on BiOBr nanosheets. The photocatalyst showed excellent degradation efficiency for glyphosate under visible-light irradiation and exhibited good reusability and stability. This work provides new insights for the design and development of 2D heterojunction photocatalysts.