High performance non-fullerene polymer solar cells based on PTB7-Th as the electron donor with 10.42% efficiency

Abstract

In this work, we present a structurally defined blue-shift non-fullerene electron acceptor (ITCT) matching with PTB7-Th as the electron donor for high-performance fullerene-free polymer solar cells (PSCs). The PTB7-Th/ITCT blend based bulk-heterojunction (BHJ) devices give an appreciable PCE of 8.23% and a relatively high V_OC of 0.96 V without any optimization. Upon device processing with thermal annealing and the addition of 0.1% DIO additive, the active layer achieves a more ordered and crystalline morphology. Consequently, a high PCE of 10.42% has been achieved with a V_OC of 0.95 V, a J_SC of 15.13 mA cm⁻² and a high FF of 0.72. To the best of our knowledge, the PCE of 10.42% is among the highest values reported in the literature to date for non-fullerene PSCs using PTB7-Th as the electron donor.