One-pot in situ synthesis of poly(3-hexylthiophene)/vanadium oxide composites

Poly(3-hexylthiophene)/vanadium oxide composites were synthesized via a onepot in situ method using oxidative polymerization and the non-hydrolytic sol-gel method. Reactions were performed at room temperature in two different solvent systems, chloroform and an 18:2 ratio of dichloromethane:nitrobenzene. Two different vanadium precursors, VCl3 and VOCl3, were investigated. Composites were characterized using matrix-assisted laser desorption/ionization mass spectrometry, powder X-ray diffraction, energy-dispersive X-ray spectroscopy coupled with scanning electron microscopy, thermal analysis, and conductivity measurements. Molecular weights varied with solvent system and vanadium precursor, generally producing masses lower than pure polymer in each respective solvent system. Samples synthesized with VOCl3 produced higher molecular weight composites than their VCl3 counterparts; however, composites synthesized with the VCl3 precursor showed superior V retention. Conductivity measurements indicated improved performance in all composites with respect to their pure polymer counterparts, with improvements up to two orders of magnitude.