ZnO_Nanorods_grown_on_cotton_fabrics_at_low_temperature-important_.pdf

/locate/cplett Chemical Physics Letters 398 (2004) 250–255ZnO Nanorods grown on cotton fabrics at low temperature Ronghua Wang, John H. Xin *, Xiao Ming Tao, Walid A. Daoud Nanotechnology Center for Functional and Intelligent Textiles and Apparel, Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Received 31 March 2004; in final form 14 September 2004 Available online 6 October 2004Abstract An effective low-temperature growth approach to grow hexagonally oriented ZnO nanorod arrays onto fibrous substrate is reported. The typical nanorods synthesized in this study were 10–50 nm in diameter and 300–500 nm in length. Meanwhile novel structural meso-scale dumbbells uniformly grown in aqueous solution were firstly discovered with the length of 2.1 lm, diameter of 700, 800 and 450 nm in a larger end face, in a smaller end face and in the waist, respectively. The cotton fabrics treated in this study provided an excellent UV protection factor rating of 50+ and therefore implied high photocatalytic activities.
2004 Elsevier B.V. All rights reserved.1. Introduction ZnO is a good candidate material for optoelectronic applications due to its wide bandgap (3.37 eV), large exciton binding energy of 60 meV, and room tempera- ture UV nanolasing action in highly ordered alignments [1–3]. Tremendous efforts have been devoted to the improvement and optimization of the synthesis of ori- ented arrays of ZnO nanowires [1–13]. The control of particle size, shape, and crystalline structure represents some of the key issues in nanotechnology and materials manufacturing [4,5]. Recently, the emphasis of the inves- tigations is on ZnO nanowires orientation, via solution approaches. In this regard, a hydrothermal process was suggested to fabricate aligned ZnO rodlike nanop- articulate thin films directly onto substrates from an aqueous solution at low temperature without seeds [6,7]. As a modification of hydrothermal methods, seeds-guided g