抄録
Smart windows refer to a glass window that enables users to intelligently control the amount of light and heat passing though; this control is made possible by an external stimulus such as voltage (electrochromic), temperature (thermochromic), ultraviolet irradiation (photochromic) and reductive or oxidizing gases (gasochromic). These technologies save energy, address CO2 concerns, improve comfort levels, and have economic benefits. The current talk presents the development of smart windows and discusses the state-of-the art in this area, with an emphasis on thermochromic materials. Due to its singular Mott type first-order transition, VO2 nanostructured films deposited onto glass substrates exhibit a unique reversible infrared modulation triggered by any external temperature stimuli. More precisely, in the infrared range, such VO2 nano-films are optically transparent and optically opaque below and above the Mott phase transition temperature, Tc ~68ºC, respectively. Such a behavior is known as thermochromism, and is an essential for application in thermochromic smart windows. This talk will introduce a novel solution method, polymer assisted deposition process, for the preparation of VO2 and VO2-based composite films. The method enables us to facially control over the film thickness, morphology and optical constants. By combining the optical design in the materials selection and/or their thickness and microstructural control, we obtained VO2 films with high visible transmittance (40-84%), controllable Mott phase transition temperatures and high switching efficiencies (max. 15.1%). The results show that the current solution process is a powerful competitor towards practical applications of this material. For further information, please read references.
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