Efficient non-fullerene organic solar cells employing aqueous solution-processed MoOas a hole-transporting layer.

Organic solar cell (OSC) has drawn considerable interest in recent decades owing to their advantages of light weight, flexible, large area and potentially low-cost. Employing an appropriate hole-transporting layer (HTL) into an OSC device has been proved as an efficient method to obtain high efficiency OSC due to the enhancement of the hole transporting and extraction of the device. In this work, aqueous solution-processed MoO(s-MoO) thin films were employed as HTLs to construct non-fullerene PM6:Y6 OSCs. The s-MoOthin film was prepared by using an aqueous solution process from an isopolymolybdate [NH]MoO.4HO precursor followed by thermal annealing treatment to convert the precursor to MoO. The s-MoOHTL based PM6:Y6 device demonstrates a power conversion efficiency of 15.75%, which is 38% improved than that of the device with thermally evaporated-MoOas HTL and 8% improved than that of the device with PEDOT:PSS as HTL. The enhancement of the device performance could be attributed to the enhanced hole mobility and better band matching of the s-MoOHTL. Moreover, the s-MoOHTL based PM6:Y6 device exhibited higher device stability than those of the reference devices. Our finding indicates that this s-MoOfilm has great potential as efficient HTL for high performance non fullerene OSCs.