High quantity and quality few-layers transition metal disulfide nanosheets from wet-milling exfoliation

Low-cost and large-area electronic applications require the deposition of active materials in simple and inexpensive techniques at room temperature; properties usually associated with polymer films. In this study, we demonstrate a simple, low-cost and environmentally friendly method for the high-yield production of two dimensional nanosheets of semiconducting transition metal disulfides, integrated with the route towards the solution-processed deposition of MoS₂ and WS₂ thin films. The resulting materials with high purity and no contamination or distortion in their structural and electronic properties were confirmed with different microscopic and macroscopic methods. As a proof of concept, we utilize these layered transition metal disulphide films as electron extraction layers in an inverted structure organic solar cell, prepared at relatively low annealing temperatures (≤150°C). A promising power conversion efficiency with high stability is achieved, which makes these proposed buffer layers quite attractive for next-generation flexible devices requiring high conductivity and transparency, as well as wide range of other potential applications.