Low-cost organic photovoltaic materials with great application potentials enabled by developing isomerized non-fused ring acceptors

Benefitting from low cost and simple synthesis, simple structured non-fused ring acceptors (NFRAs) and polymer donors are crucial for the application of organic solar cells (OSCs). Herein, two isomerized NFRAs, namely 4T-FClFCl and 4T-2F2Cl, are designed with end-group engineering, which modulates the electrostatic potential distributions and crystallinity of acceptors, and accordingly, the A/A and D/A intermolecular interactions. The OSC based on 4T-2F2Cl with strong D/A interactions shows a record-high efficiency of 16.31% in blending with a low-cost polymer donor PTQ10, which shapes obviously improved bulkheterojunction (BHJ) networks blade-coated by non-halogenated solvent o-xylene, and thus significantly diminishes non-radiative recombination loss. A higher industrial figure of merit (i-FOM) of 0.46 for PTQ10:4T-2F2Cl in comparison with PTQ10:4T-FClFCl (i-FOM=0.29) is demonstrated owing to its superior device efficiency and operational stability. Note that the i-FOM of PTQ10:4T-2F2Cl is the highest value for OSCs reported so far. This work deepens the synergistic effect of the A/A and D/A interactions on achieving desired bulk heterojunction morphology and demonstrates a printable photovoltaic system for low-cost, high-efficiency, stable, and eco-friendly OSCs.