Hydrothermal growth of few layer 2H-MoS2 for heterojunction photodetector and visible light induced photocatalytic applications†
The present low yielding growth techniques of semiconducting 2H phase molybdenum disulfide (MoS2) hamper its widespread applications. In this article, we report a novel hydrothermal chemical approach to synthesize micron sized few layer 2H-MoS2 on a large scale. Sodium molybdate and ammonium thiocyanate have been used as precursors to obtain template-free 2H-MoS2 in solution. Detailed microscopic and spectroscopic characterizations reveal that the bottom-up synthesized few layer MoS2 flakes are highly crystalline having the hexagonal 2H phase. Photodetector devices comprising a p-type silicon (p-Si)/n-MoS2 heterostructure have been fabricated for the first time using solution processed 2H-MoS2 synthesized by the bottom up approach. The heterojunction diode exhibits a high rectification ratio (>103) with broad band photoresponse over the visible range. Because of the visible light photoresponse, as-synthesized MoS2 along with reduced graphene oxide (MoS2–RGO hybrids) have been utilized to study the potential of this two dimensional (2D) heterostructure for visible light driven photocatalytic Rhodamine B dye degradation. This study demonstrates the potential of solution processed MoS2 for integration with silicon and growth of 2D heterostructures for visible light induced multifunctional applications.