New molecular design towards high performance single junction organic solar cell (Conference Presentation)

Recently, non-fullerene n-type organic semiconductors (n-OS) have attracted significant attention as acceptors in organic photovoltaics (OPVs) due to their great potential to realize high power conversion efficiencies (PCEs). In this regard, a rational design of central fused ring unit of the n-OS molecules is crucial to maximize the state-of-the-art PCEs. Here, we report a new class of n-OS acceptor, Y series, that employ a ladder-type electron-deficient-core-based central fused ring to fine tune its absorption and energy levels. Among these new acceptors, the Y6-based OPVs exhibit a high efficiency of 15.7 % (both in conventional or inverted structures), and a certified efficiency of 14.9 % by an inverted structure. The electron-deficient-core-based fused ring reported in this work opens a new way in the molecular design of high performance n-OS acceptors for OPVs. References: [1] Nat. Commun., 2019, 10: 570 [2] Adv.Mater., 2019, 31: 1807577 [3] Joule, 2019, 4:1140-1151