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Finding high efficiency fullerene-free organic acceptor material is a hot researching field in organic solar cells.A strategy in molecular designing is to imitate the isotropic structure of fullerene to achieve high carrier mobility.So 1,3,5-tribromobenzene is introduced to build the star-shaped molecule.Diketopyrrolopyrrole(DPP)derivatives are widely used in many donor materials.However its high LUMO level limits the application in acceptor materials.And dicyanovinyl is a strong electron-withdrawing moiety which can be easily modified to efficiently lower the LUMO level of materials while maintaining or reducing band gap.Therefore new conjugated small molecules Ph(DPPBDCN)3 has been prepared,and the OSCs device with PTB7-Th as the donor gets a PCE of 2.13%.