Recent replies to "Visible Light Photocatalysis via CdS/TiO2 Nanocomposite Materials" http://network.nature.com/forums/nanotechnology/122 en-us 40 <p>Complementing,<br />Studies have proven that with the appropriate particle interaction, CdS-TiO2 nanocomposites can efficiently decompose organics such as phenol and methylene blue under visible light irradiation less than 495nm.<br />The reaction occurs when a CdS particle is excited by a photon with a wavelength less than 495 nm. An <span class="caps">EHP</span> is formed, and subsequently the photogenerated electron is quickly transferred to the conduction band of a coupled TiO2 particle that has a conduction band edge more positive than the CdS particle (∼ 0.5 eV). The photogenerated hole in the quantum-sized CdS particle can<br />theoretically migrate to the surface and participate in the oxidation of adsorbed organics. The electrons that are transferred to the conduction band of TiO2 have no holes to recombine with and therefore participate in reduction reactions according to the conduction band energy level of TiO2. In order to establish a quantum size effect, one must have to synthesize extremely small particles of the order of the excitonic diameter and to stabilize them against further growth. Reversemicelle process provides a controlled environment to achieve this goal. Reverse micelles are thermodynamically stable structures which consist of a nanometer-sized spherical water core that is encapsulated by surfactant molecules in a nonpolar medium.</p> Fri, 28 Dec 2007 20:05:23 -0000 http://network.nature.com/forums/nanotechnology/122?page=1#reply-1942 Ferreira, Fabio A. S. http://network.nature.com/forums/nanotechnology/122?page=1#reply-1942 <p>Thank you for comment <strong>Aparna</strong>,<br />Photocatalytic experiments using visible light and a combination of UV-A and visible light were performed using a single lamp and an annular reflector to provide irradiation. <span class="caps">A 1000W</span> metal halide lamp was experimentally chosen, since it adequately replicated both the pattern and intensity peaks of the solar spectrum more accurately than other visible sources such as high-pressure sodium and fluorescent lamps.</p> Fri, 28 Dec 2007 19:56:49 -0000 http://network.nature.com/forums/nanotechnology/122?page=1#reply-1940 Ferreira, Fabio A. S. http://network.nature.com/forums/nanotechnology/122?page=1#reply-1940 <p>hi can you tell me what kind of lamp you used for this experiment</p> Thu, 29 Nov 2007 20:53:33 -0000 http://network.nature.com/forums/nanotechnology/122?page=1#reply-1698 aparna iyer http://network.nature.com/forums/nanotechnology/122?page=1#reply-1698