Počet záznamů: 1

Tuning the conduction mechanism in niobium-doped titania nanoparticle networks

  1. 1.
    0361372 - FZU-D 2012 RIV US eng J - Článek v odborném periodiku
    Němec, Hynek - Mics, Zoltan - Kempa, Martin - Kužel, Petr - Hayden, O. - Liu, Y. - Bein, T. - Fattakhova-Rohlfing, D.
    Tuning the conduction mechanism in niobium-doped titania nanoparticle networks.
    Journal of Physical Chemistry C. Roč. 115, č. 14 (2011), s. 6968-6974 ISSN 1932-7447
    Grant CEP: GA ČR(CZ) GP202/09/P099; GA AV ČR(CZ) IAA100100902
    Výzkumný záměr: CEZ:AV0Z10100520
    Klíčová slova: time-domain terahertz spectroscopy * electron transport * transparent conductors * doped TiO2
    Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
    Impakt faktor: 4.805, rok: 2011

    Networks of niobium-doped TiO2 anatase nanoparticles with variable doping concentrations were investigated by time-domain terahertz spectroscopy and microwave impedance spectroscopy. A detailed description of their electromagnetic response is proposed; the model takes into account the depolarization fields of inhomogeneous samples and allows us to understand the conductive and dielectric response of individual nanoparticles. We find that electron hopping is the dominating contribution to the conductivity at terahertz frequencies and that the dielectric losses of TiO2 nanoparticles are enhanced in comparison with bulk anatase. The conductive properties of nanoparticles can be tuned via synthesis conditions and thermal posttreatment. In particular, annealing at elevated temperatures improves the nanoparticle crystallinity, reduces the density of structural defects, and enhances the conductive percolation of the network.
    Trvalý link: http://hdl.handle.net/11104/0198695