Improving photovoltaic properties of linear small molecules with TPA–DPP segment by tuning their frameworks

Three low band-gap small molecules (SMs) with D–A, D–A–D and D–A–B–A–D frameworks, namely TPA–DPP, TPA2DPP and (TPADPP)2AN, were designed and synthesized, in which triphenylamine (TPA), 3,6-dithienyldiketopyrrolopyrrole (DPP) and 9,10-anthracene (AN) were used as donor (D), acceptor (A) and bridge (B) segments, respectively. Their optical, thermal, electrochemical and photovoltaic properties were investigated. Significant influence of different...