A novel A-D-A type small molecule (DTP-2EH-IO2Cl) incorporating dithiophenepyrrole (DTP) core with indene-dione (IO2Cl) side chain with an intermediate band gap and rigid structure is incorporated into polymer donor PM6 and one of the three A−DA′D−A small molecule acceptor—L8-BO, BTP-eC9 or Y6—for ternary-blend organic photovoltaics (OPVs). The third component DTP-2EH-IO2Cl induces not only energy transfer but also stronger molecular packing of the acceptors, resulting in a larger coherence length and enhanced absorption that enhances devices’ power conversion efficiencies (PCE) and thermal stability.
