Rajaraman Ramakrishnan,Sudha J. Devaki*,A. Aashish, Senoy Thomas, Manoj Raama Varma, Najiya KPP
Nanostructured Semiconducting PEDOT−TiO2/ZnO Hybrid Composites for Nanodevice Applications
In this paper, we have developed a simple strategy for the preparation of hybrid nanocomposites of poly(3,4-ethylenedioxythiophene)–TiO2/ZnO (PZT) and demonstrated its application in a thermoelectric device. Hierarchical hetero-nanostructured TiO2/ZnO (ZTO) was prepared by a facile sol–gel process in the presence of a biocapping agent. PZT was prepared by in situ polymerization of EDOT in the presence of ZTO. It was characterized by UV–visible, FT-IR, XRD, Raman, SEM, TEM, and AFM analyses. Results revealed homogeneous distribution of ZTO with a heterocrystalline phase of wurtzite ZnO/anatase TiO2 having high density of various defects in the hybrid nanocomposite. Studies showed that ZTO is excellently interfaced with highly ordered self-assembled extended π-layers of PEDOT chains, which could enhance the charge carrier concentration (3.92 × 1020 cm–3) and charge carrier mobility (0.83 cm2 V–1 s–1). Furthermore, we have demonstrated its application as a thermoelectric material by fabricating the device (Cu/PZT/Cu), which showed low thermal conductivity of 0.0495 Wm–1K–1, Seebeck coefficient of 19.05 μV K–1, power factor of 1.28 μW m–1K–2, and figure of merit of 4.8 × 10–3 at ambient temperature. All of these excellent material properties of PZT suggest its application as an active material for the fabrication of nanoelectronic devices with large area.
J. Phys. Chem. C, 2016120 (8), pp 4199–4210