PEDOT:PSS‐Assisted Exfoliation and Functionalization of 2D Nanosheets for High‐Performance Organic Solar Cells

Here, a facial and scalable method for efficient exfoliation of bulk transition metal dichalcogenides (TMD) and graphite in aqueous solution with poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to prepare single‐ and few‐layer nanosheets is demonstrated. Importantly, these TMD nanosheets retain the single crystalline characteristic, which is essential for application in organic solar cells (OSCs). The hybrid PEDOT:PSS/WS₂ ink prepared by a simple centrifugation is directly integrated as a hole extraction layer for high‐performance OSCs. Compared with PEDOT:PSS, the PEDOT:PSS/WS₂‐based devices provide a remarkable power conversion efficiency due to the “island” morphology and benzoid–quinoid transition. This study not only demonstrates a novel method for preparing single‐ and few‐layer TMD and graphene nanosheets but also paves a way for their applications without further complicated processing.