“…As one of the promising photovoltaic technologies for addressing energy and environmental issues, organic solar cells (OSCs) have the characteristics of low cost, flexibility, lightweightness, environmental friendliness, large-area printing manufacture, etc. 1â5 To date, the power conversion efficiency (PCE) of OSCs has reached remarkable values exceeding 19% owing to the invention of new active layer materials, especially non-fullerene acceptors (NFAs) with acceptorâdonorâacceptor (AâDâA) architectures 6â13 and efficient morphology control 14â18 for device fabrication and optimization. In the past decade, side chain engineering has proven to be an efficient method for the delicate design of active layer materials and precise regulation of the corresponding morphology because solubility, 19,20 crystallization 21 and packing modes, 22,23 etc.…”