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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2008.12.009 Byline: Todd P. Otanicar (a), Patrick E. Phelan (a), Jay S. Golden (b)(c) Keywords: Optical properties; Fluids; Solar thermal energy Abstract: A method for experimentally determining the extinction index of four liquids (water, ethylene glycol, propylene glycol, and Therminol VP-1) commonly used in solar thermal energy applications was developed. In addition to the extinction index, we report the refractive indices available within the literature for these four fluids. The final value reported is the solar-weighted absorption coefficient for the fluids demonstrating each fluid's baseline capacity for absorbing solar energy. Water is shown to be the best absorber of solar energy of the four fluids, but it is still a weak absorber, only absorbing 13% of the energy. These values represent the baseline potential for a fluid to be utilized in a direct absorption solar thermal collector. Author Affiliation: (a) Department of Mechanical and Aerospace Engineering, National Center of Excellence on SMART Innovations, Arizona State University, P.O. Box 876106, Tempe, AZ 85287-6106, USA (b) Department of Civil and Environmental Engineering, National Center of Excellence on SMART Innovations, Arizona State University, P.O. Box 876106, Tempe, AZ 85287-6106, USA (c) School of Sustainability, National Center of Excellence on SMART Innovations, Arizona State University, P.O. Box 876106, Tempe, AZ 85287-6106, USA Article History: Received 2 June 2008; Revised 25 November 2008; Accepted 21 December 2008 Article Note: (miscellaneous) Communicated by: Associate Editor Darren Bagnall

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2005.04.013 Byline: A.V. Kokate, U.B. Suryavanshi, C.H. Bhosale Keywords: Electrodeposition; CdSe thin films; PEC characterization; Optical absorption Abstract: In the recent years, cadmium chalcogenide compounds have been extensively investigated because of their potential applications in solar energy conversion. Thin films of CdSe have been deposited onto the stainless steel and fluorine doped tin oxide (FTO) coated glass substrates using simple and inexpensive electrodeposition technique. The non-aqueous solvent ethylene glycol (CH.sub.2OHCH.sub.2OH) containing precursors of Cd and Se with ethylenediaminetetraacetic acid (EDTA) tetra sodium salt as a complexing agent is used to obtain stoichiometric deposits. Deposition potential was estimated from polarization curves and other preparative parameters such as bath temperature and concentration of solution were optimized. X-ray diffraction (XRD) analysis reveals that the films are polycrystalline with cubic structure. PEC study shows the CdSe films are photoactive. Optical absorption study shows the presence of direct transition with band gap energy 1.72eV. The energy dispersive analysis by X-rays (EDAX) reveals that the substrate is well covered with large number of grains indicating compact structure. The average ratio of the atomic percentage of Cd:Se is 50.31:49.69, showing that the deposited films are almost stoichiometric. Author Affiliation: Electrochemical Materials Research Laboratory, Department of Physics, Shivaji University, Kolhapur 416 004, India Article History: Received 1 November 2004; Revised 20 April 2005; Accepted 25 April 2005 Article Note: (miscellaneous) Communicated by: Associate Editor Xavier Matthew