Efficient non-fullerene polymer solar cells enabled by tetrahedron-shaped core based 3D-structure small-molecular electron acceptors

Here we report a series of tetraphenyl carbon-group (tetraphenylmethane (TPC), tetraphenylsilane (TPSi) and tetraphenylgermane (TPGe)) core based 3D-structure non-fullerene electron acceptors, enabling efficient polymer solar cells with a power conversion efficiency (PCE) of up to similar to 4.3%. The results showthat TPC and TPSi corebased polymer solar cells (PSCs) perform significantly better than that based on TPGe. Our study provides a new approach for designing small molecular acceptor materials for polymer solar cells.