Over 31% efficient indoor organic photovoltaics enabled by simultaneously reduced trap-assisted recombination and non-radiative recombination voltage loss
Xiaobo Zhou, Hongbo Wu, Urvashi Bothra, Xingze Chen, Guanyu Lu, Heng Zhao, Chao Zhao, Qun Luo, Guanghao Lu, Ke Zhou, Dinesh Kabra, Zaifei Ma, Wei Ma
Abstract
a layer-by-layer (LBL) processing strategy, low leakage current and low non-radiative recombination loss can be synergistically achieved in PM6:Y6-O based devices. Detailed characterizations reveal the stronger crystallinity, purer domains and ideal interfacial contacts in the LBL devices compared to their bulk-heterojunction (BHJ) counterparts. The optimized morphology yields a reduced voltage loss and an impressive FF of 81.5%, and thus contributes to a high PCE of 31.2% under a 1000 lux light-emitting diode (LED) illumination in the LBL devices, which is the best reported efficiency for indoor OPVs. Additionally, this LBL strategy exhibits great universality in promoting the performance of indoor OPVs, as exemplified by three other non-fullerene acceptor systems. This work provides guidelines for morphology optimization and synergistically promotes the fast development of efficient indoor OPVs.