Polymer solar cells(PSCs)based on non-fullerene acceptors,also known as fullerene-free PSCs(NF-PSCs),have great potentials in achieving broad and strong optical absorption and favorable molecular energy level alignment in their active layers.In comparison with fullerene-based acceptors,the NF-acceptors generally possess anisotropic conjugated backbones and exhibited very different properties when blended with varied conjugated polymer donors.Therefore,we need to design new conjugated polymers for achieving highly efficient NF-PSCs.