Synthesis and characterization of new nonfullerene electron acceptors with a chrysene core

The utilization of non-fullerene acceptors has greatly promoted the development of organic photovoltaics in past few years. Herein, two new non-fullerene small-molecule electron acceptors, CRIC and CRIC-4F, with a four-fused-rings containing chrysene core, are designed and synthesized. Benefiting from the rigid and planar chrysene segment, these two acceptors exhibit strong intramolecular it electron transition with intense optical absorption from 550 to 750 nm. Both molecules present deep lowest unoccupied molecular orbital (LUMO) energy levels at around -4.0 eV, thereby making them suitable to employ as electron acceptors. In combination with electron donor J52-2F, organic solar cells based on CRIC achieved a decent power conversion efficiency (PCE) of 6.12% with a low energy loss of 0.59 eV owning to their complementary absorption, higher energy levels, and reduced charge recombination, thus surpassing the J52-2F:CRIC-4F based counterpart (PCE = 5.61%). This work demonstrates that chrysene derivatives are potential acceptors for applications in organic photovoltaics with low energy losses.