Cost-effective scalable synthesis of few layers MoS2 based thin film for sunlight enforced photocatalytic activity

Two-dimensional (2D) semiconductor nanostructures have gained tremendous interest in the field of environmental remediation and water purification. Nanostructures coated surfaces provide new insight for the development of cost-effective advanced photocatalyst. In this study, 2D-MoS2 nanosheets based coating has been developed through the combined effort of the exfoliation and a spin coating method. Microscopy analysis inferred the formation of nanosheets from the bulk structured MoS2 with the reduction in their average dimensions. Exfoliated MoS2 nanosheets formed in 18 h reaction time has average length similar to 1019 nm and width similar to 544 nm. Cross-sectional SEM studies confirm the formation of MoS2-PVA thin films with different orientation of MoS2 nanosheets. UV-Vis absorption spectroscopy studies exhibit two peaks at 619 nm and 680 nm with improved optical absorption. The XRD and Raman spectroscopy analysis reveals the 2H-phase of MoS2 nanosheets. 2D-MoS2-PVA composite thin film was tested as an advanced photocatalyst coating for the breakdown of methylene blue (MB) and malachite green (MG) pollutant molecules under sunlight. 2D-MoS2-PVA composite thin film decomposed the 5 mu M solution of MB and MG molecule solutions in 80 min and 40 min, respectively, under sunlight (800 W/cm(2)). The efficient photodegradation performance of the 2D-MoS2-PVA composite indicates their potential usage in other environmental applications.