Synthesis and electronic properties of thiadiazole[3,4-c]pyridine copolymers for solar cell application

Abstract

Two novel conjugated polymers P1, P2 containing dithienothiadiazole[3,4-c]pyridine acceptor and benzodithiophene, naphthodithiophene donors were synthesized by Stille reaction. The polymers were characterized by H-1 NMR, GPC, and elemental analysis. The optical band gaps for Pl, P2 were found to be 1.67 and 1.60 eV. The electrochemical studies of P1, P2 revealed the HOMO and LUMO energy levels of the polymer were -5.07, -5.13 eV, and -3.40, -3.53 eV respectively. The polymers are thermally stable up to 380-405 degrees C. Optoelectronic investigation and electrical properties of fabricated organic field effect transistor (OFET) suggest these polymers can be potential candidates for organic solar cell application.