Aryl-substituted-indanone end-capped nonfullerene acceptors for organic solar cells with a low nonradiative loss.

Three nonfullerene acceptors with different aryl-substituted terminal groups were designed and synthesized. The optimal device obtained a PCE of 11.42%, with a nonradiative energy loss ≤0.16 eV. Non-rigid π-extension of terminal groups is proved to be a feasible strategy to modulate the molecular packing behaviour and reduce nonradiative recombination loss.