A polythiophene derivative with dioctyloxyltriphenylamine-vinylene conjugated side chain: Synthesis, hole mobility, and photovoltaic property

Abstract

A new polythiophene derivative with dioctyloxyl triphenylamine-vinylene (DOTPAV) conjugated side-chain, DOTPAV-PT, was synthesized by the Stille coupling method and characterized by 1H-NMR, 13C-NMR, elemental analysis, gel permeation chromatography, thermogravimetric analysis, UV-vis absorption spectroscopy, photoluminescence spectroscopy, and cyclic voltammetry. The polymer DOTPAV-PT is soluble in common organic solvents and possesses good thermal stability with 5% weight loss temperature of 310°C. The weight-average molecular weight of DOTPAV-PT is 8.0 K with a polydispersity index of 1.24. The hole mobility of the polymer determined from space-charge-limited current model was 1.25 x 10-4 cm2 V-1 s-1. The bulk heterojunction polymer solar cell with the configuration of ITO/PEDOT : PSS/polymer : PCBM (1 : 1)/Ca/Al was fabricated, and the power conversion efficiency of the device was 0.16% under the illumination of AM1.5, 100 mW cm-2. © 2009 Wiley Periodicals, Inc.