Abstract: By considering the continuous emergence of global energy crisis, several advanced building technologies aim to develop a “zero-energy home” (ZEH) based on renewable energy devices and energy-saving materials. The same strategy can be used to develop low-energy transportation. In order to realize the above goals in the near future and to relieve the urgent need of energy, R&D in “smart windows” with the capability of automatic daylighting control is of much importance. Electrochromic windows (ECWs) can modulate solar transmission reversibly by applying low dc bias and then control the interior solar heating. Hence, the energy or electricity required for air conditioning and lighting can be significantly reduced. As a consequence, ECWs are of great commercial value for the applications in ordinary housing, commercial buildings, greenhouses, automobiles, public transport, ships, aircrafts, and so on. Here we propose a two-year energy tech plan (2007-2008) to develop novel ECW systems with high energy-saving efficiency using a nanostructured indium hexacyanoferrate (InHCF) counter electrode. When using pseudo-transparent InHCF, the working electrode does not need precoloration and polarization during device assembly. Hence, the assembly process can be simplified, and the system stability can be enhanced correspondingly. Besides, the ECW systems developed by this plan will be advantageous for the patent application since InHCF is a relatively new material. In the first year (2007), we will focus on the parallel development of multiple pilot ECW systems by matching the nanostructured InHCF counter electrode with appropriate solid polymer electrolytes and high-coloration-efficiency working electrode materials, such as transition metal oxides, transition metal cyanides, organic bipyridines, and conducting polymers. The results will provide informative clues for high-energy-saving system screening and full-size window development in the next stage (2008).
indium hexacyanoferrate (InHCF)