Intermixing of MoS₂ and WS₂ photocatalysts toward methylene blue photodegradation

Visible-light-driven photocatalysis using layered materials has garnered increasing attention regarding the degradation of organic dyes. Herein, transition-metal dichalcogenides MoS₂ and WS₂ prepared by chemical vapor deposition as well as their intermixing are evaluated for photodegradation (PD) of methylene blue under solar simulator irradiation. Our findings revealed that WS₂ exhibited the highest PD efficiency of 67.6% and achieved an impressive PD rate constant of 6.1 × 10^-3 min^-1. Conversely, MoS₂ displayed a somewhat lower PD performance of 43.5% but demonstrated remarkable stability. The intriguing result of this study relies on the synergetic effect observed when both MoS₂ and WS₂ are combined in a ratio of 20% of MoS₂ and 80% of WS₂. This precise blend resulted in an optimized PD efficiency and exceptional stability reaching 97% upon several cycles. This finding underscores the advantageous outcomes of intermixing WS₂ and MoS₂, shedding light on the development of an efficient and enduring photocatalyst for visible-light-driven photodegradation of methylene blue.