Diketo-Pyrrolo Pyrrole-Based Acceptor-Acceptor Copolymers with Deep HOMO and LUMO Levels Absorbing in the Near Infrared

A series of acceptor-acceptor (A-A’) alternated copolymers based on dithienodiketopyrrolo pyrrole were synthesized by copolymerizing it with itself and other different electron-poor monomers. The experimental computed optoelectronic properties four DPP-based copolymers, P(DPP-DPP) (with linear branched chains), copolymer diazapentalene P(DPP-DAP) also dioxothienopyrrolebenzodifurandione P(DPP-BTPBF), as well thermal characterizations described. UV-visible spectrophotometry cyclic voltammetry used to estimate the optical electrochemical bandgaps, found very small: 1.3, 1.0, 0.9 eV for P(DPP-DPP), P(DPP-DAP), respectively. BTPBF unit allowed a strong reduction bandgap, leading broad absorption in visible near infra-red regions from 650 1450 nm. These results compared analogous donor-acceptor (D-A) previously reported, which DPP is replaced DTS, P(DTS-DPP), P(DTS-DAP), P(DTS-BTPBF). same trend was observed. By comparing A-A’ D-A’ analogues, shown that bandgap remained while both HOMO LUMO levels lowered roughly 0.2 eV.