Synthesis, characterization, and applications in photovoltaic cells of oxetane-functionalized P3HT derivatives

Abstract

Several crosslinkable oxetane-functionalized copolymers, containing regio-regular segments of 3-hexylthiophene, are synthesized using the Grignard metathesis polymerization. The optical and electrochemical properties of the new polymers, both in the soluble and crosslinked forms, are reported. These polymers are used in the preparation of organic photovoltaics upon blending with PCBM as electron-acceptor. The effect of the crosslinking of these copolymers, once the blend films are formed, on the devices performance is also studied. In particular, the insertion of the oxetane-functionalized thiophene comonomers leads to a decrease of the devices performance, which is further decreased upon crosslinking of the copolymer. However, the stability of the devices overall improves upon crosslinking of the copolymer. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 652–663