Polythiophene Derivative with the Simplest Conjugated-Side-Chain of Alkenyl: Synthesis and Applications in Polymer Solar Cells and Field-Effect Transistors

摘要

A polythiophene derivative with the simplest conjugated side chain, poly(3-hexy-1-enylthiophene) (P3HET), was synthesized by Stille self-coupling reaction. A comparative study of the newly synthesized polymer with poly(3-hexylthiophene) (P3HT), one of the most widely investigated optoelectronic materials, is presented. The effect of double bond (C=C) on the side chain toward thermal stability and optical and electronic properties was fully characterized by TGA, UV— vis absorption spectroscopy, photoluminescence spectroscopy, and cyclic voltamrnetry. The hole mobility of P3HET determined by the space—charge-limited current (SCLC) model is 6.7 x 10~(-3) cm~2/V s, which is comparable to P3HT with similar molecular weight and regularity and 1 order of magnitude higher than most conjugated-side-chain polythiophene derivatives. Polymer solar cells (PSCs) and field effect transistors (FETs) were fabricated respectively to exploit its potential applications in optoelectronic devices.