Spray standardized interfacial layer for high performance organic solar cells across diverse active layer systems

Abstract

Abstract Constructing highly ordered molecular frameworks through effective interfacial engineering is crucial for high-performance organic solar cells (OSCs). However, most advanced interfacial layers rely on complex, multistep procedures, limiting broader implementation and process standardization across different active layer systems. Here, we demonstrate ultrasonic spray coating of poly(3,4-ethylenedioxy thiophene):polystyrene sulfonate (PEDOT:PSS) as a unified interfacial engineering strategy for OSCs, achieving universal compatibility with diverse active layer systems, from typical fullerene (PC 71 BM) to state-of-the-art non-fullerene (IT-series and Y-series) acceptors. Compared to spin coating, spray-coated PEDOT:PSS OSCs enhance molecular crystallinity, structural ordering, and charge transport, delivering equivalent or superior photovoltaic performance across all representative active layer systems, demonstrating that spray coating provides a unified, widely applicable protocol for PEDOT:PSS interfacial layer fabrication. By eliminating intricate processes and standardizing the interface fabrication procedure, this work highlights the significant potential of this facile and versatile deposition technique for generalizable interfacial fabrication in OSCs, offering valuable insights and practical guidance for advancing high-performance devices across diverse systems.