%0 Journal Article
%T Growth of Horizontal Nanopillars of CuO on NiO/ITO Surfaces
%A Siddharth Joshi
%A Mrunmaya Mudigere
%A L. Krishnamurthy
%A G. L. Shekar
%J Journal of Nanoscience
%D 2014
%R 10.1155/2014/635308
%X We have demonstrated hydrothermal synthesis of rectangular pillar-like CuO nanostructures at low temperature (~60¡ãC) by selective growth on top of NiO porous structures film deposited using chemical bath deposition method at room temperature using indium tin oxide (ITO) coated glass plate as a substrate. The growth of CuO not only filled the NiO porous structures but also formed the big nanopillars/nanowalls on top of NiO surface. These nanopillars could have significant use in nanoelectronics devices or can also be used as p-type conducting wires. The present study is limited to the surface morphology studies of the thin nanostructured layers of NiO/CuO composite materials. Structural, morphological, and absorption measurement of the CuO/NiO heterojunction were studied using state-of-the-art techniques like X-ray diffraction (XRD), transmission electron microscopy (SEM), atomic force microscopy (AFM), and UV spectroscopy. The CuO nanopillars/nanowalls have the structure in order of (5£¿¡À£¿1.0)£¿¦Ìm ¡Á (2.0£¿¡À£¿0.3) ¦Ìm; this will help to provide efficient charge transport in between the different semiconducting layers. The energy band gap of NiO and CuO was also calculated based on UV measurements and discussed. 1. Introduction In the modern society, environmental and energy resource concerns have been increasing, and because of that, greater stress has been placed on development of renewable energy resources especially on solar energy based photovoltaic cells, whose economic feasibility relies on efficient collection, retention, and utilization of photons. Over the past decade, research on solar cell has become one of the hot topics within science and engineering [1¨C3]. The need for higher solar cell efficiencies at lower cost has become apparent, and at the same time synthetic control of nanostructures using top-down/bottom-up approaches has improved such that the high performance electronic devices are becoming possible [4, 5]. Inorganic nanostructures [6] with tailored geometry over their organic counterparts are expected to play significant roles for the next-generation nanoscale electronic, optoelectronic, electrochemical, and electromechanical devices [7¨C10]. Copper oxides (CuO and Cu2O) are p-type semiconductor oxides, suitable materials for high efficiency solar cells due to their band gap of 1.3 and 2.0£¿eV, respectively, which are close to the ideal energy gap for solar cells, and well matched with the solar spectrum. CuO has been intensively studied for photovoltaic/sensing devices due to its rich family of nanostructures and promising
%U http://www.hindawi.com/journals/jns/2014/635308/