Synthesis and Characterization of p-Type Poly(2,7-carbazole) Materials for Solar Cells

π-Conjugated light emitting polymers are having very wide applications in many areas, especially in optoelectronic, photonic and renewable energy systems. 2,7-substituted polycarbazoles are excellent p-type candidates with great potential toward these applications. However, very few reports were published in literature about the applicability of poly(2,7-carbazoles) which is attributed to the difficulties in direct functionality at 2,7-positions (meta-). In the present work, we report the synthesis of a 2,7-dibromo-substituted polycarbazole (poly(N-dodecylcarbazole)-2,7-diyl) material via four different consecutive steps. In first two steps, the basic 2,7-substitution was made by using commercial dibromobiphenyl and then the monomeric dodecylcarbazole was synthesized by nucleophilic substitution in the third step. Finally, the titled polymer was synthesized by Yamamoto polymerization. The structures of the intermediate products are confirmed by FTIR. The monomer and polymer were characterized by FTIR, UV-vis, emission and NMR techniques. The polymer has shown broad absorption comparing to the parent 2,7-dibromo-substituted-carbazole and monomeric dodecylcarbazole. Similarly, PCbz has exhibited strong excimer emission in all of the most commonly used organic solvents. Nevertheless, owing to the attractive tunable optical properties poly(2,7-carbazoles) and derivatives, they could be used as smart materials for electroactive and photonic device architectures. Keywords: Carbazole, Dodecylcarbazole, Poly(dodecylcarbazole), Excimer