One-pot synthesis of gold/poly(3,4-ethylendioxythiophene) nanocomposite

In this paper, we report the preparation of highly stable gold nanoparticles/poly(3,4-ethylendioxythiophene) nanocomposites by a one-pot chemical route in aqueous medium without surfactants to increase the solubility of the monomer (3,4-ethylendioxythiophene, EDOT) or to stabilize gold nanoparticles (Au NPs). The generation of the nanocomposite was followed by UV–Visible transmission spectroscopy combined with multivariate curve resolution alternating least squares analysis to deconvolute the individual spectra of the different species generated in the synthesis: oligomers, polymer and gold nanoparticles. The plasmon band observed at 530 nm during the synthesis step indicates the generation of gold nanoparticles. The influence of monomer and metal precursor concentration and their concentration ratios on Au NP size were analyzed. The electrochromic properties of the composite were investigated by UV–Visible absorption spectroelectrochemistry, being mainly related to polymer oxidation and reduction. The main difference observed is the hypsochromic shift of the polymer spectra due to the gold nanoparticles inside the polymer. Multicyclic spectroelectrochemical experiments evidence a high stability and adhesion of the nanocomposite.