Synthesis of random copolymer using Zig-Zag Naphthodithiophene for bulk Heterojunction polymer solar cell applications

Abstract

Synthesized a random copolymer here, namely P(zNDT-TPDBT), consisting of an electron-rich unit ‘zig-zag’ 4,9-bis-(2-ethylhexyloxy)naphtho[1,2-b:5,6-b’]dithiophene (zNDT) and different ratio of two-electron acceptor units of thieno[3,4-c]pyrrole-4,6-dione (TPD) and benzodiathiazole (BT) via Stille coupling polymerization. The photophysical, electrochemical, and photovoltaic properties of P(zNDT-TPDBT) were investigated. The differences in the photophysical property of P(zNDT-TPDBT) indicate (i) red-shifted and broadening absorption spectrum located at 509 nm in thin-film as compared to solution (λmax = 492 nm) (ii) the fluorescence spectrum shows dual emission bands at 545 nm and 608 nm in th..