In this paper, for the first time, a TiO2 submicron-diameter wire suspension-based smart window device is demonstrated in which combined planar and finger electrodes are utilised to reversibly change the orientation of the nanowires. Electrospun TiO2 anatase submicron-diameter wire suspensions in a viscous polydimethylsiloxane (PDMS) matrix were prepared directly from electrospun submicron-diameter fibre mats by using high-shear mixing, achieving the complete break-up of all electrospun mats and suspending TiO2 submicron-diameter wires uniformly in the PDMS matrix. Suspension was used as an active layer in an electro-optical device where a reversible change in light scattering is achieved by preparing a device consisting of an active layer and combined planar and finger electrode system. Using the constructed device, it was possible to change the alignment or spatial distribution of TiO2 submicron-diameter wires by applying a DC electric field across the planar or finger, electrodes thus changing the transmittance (ΔT = 25%) of the suspension and demonstrating the potential to use combined planar and finger electrode devices in smart window applications.

Al doped ZnO is used as a material for transparent conductive electrodes in solar energy and display screen applications, as well as semiconducting material in electronic and photonic devices. For effective use it is essential to control the electrical and optical properties of ZnO:Al thin films. In order to investigate the influence of oxygen environment on effective Al solubility and intrinsic defects introduced at high doping levels during the film growth, ZnO:Al thin films were deposited in vacuum and oxygen background by pulsed laser deposition method. Films were doped with varying Al concentrations by using targets with Al doping levels of 1-10 at%. In vacuum, substantially increased free electron concentrations were observed for all Al doping levels, which indicates that the formation of acceptor-type defects, acting as electron killer centers, was largely suppressed during the growth in oxygen-poor conditions. The dependence of carrier mobility from Al concentration was also greatly influenced by oxygen conditions during the film growth, suggesting that ionized impurity concentrations in the films deposited in vacuum and oxygen background were significantly different. The results were interpreted in the context of intrinsic acceptortype defects Vzn (zinc vacancy), which concentration is strongly modified by the presence of oxygen during the film deposition. These vacancies are assumed to influence free electron concentration and electron mobility by acting as deep electron acceptors and charged electron scattering centers (V-zn(2-)). (C) 2014 Elsevier B.V. All rights reserved.

Here we report the results of structural, microstructural and magnetic property characterizations of both thin films and bulk samples of LaMnO3 (LMO). Thin films were deposited by the atomic layer deposition technique on silicon (1 0 0) substrates, whereas bulk samples were prepared by a citrate combustion route. Effects of varying thickness, annealing atmosphere and temperature were studied on both LMO sample classes. Single-phase perovskite crystal structure was confirmed by x- ray diffraction and Raman spectroscopy, in thin films annealed at 700 and 800 degrees C as well as in bulk samples. Thin films annealed in N-2 or O-2 atmosphere do not vary in the crystal structure, but differ by the oxygen stoichiometry, microstructure and magnetic properties. The Curie temperature in all LMO thin films annealed in N-2 was found to be around 200 K, while it was around 250 K for the films annealed in O-2 as well as for the bulk samples.