NEAR ROOM-TEMPERATURE DEPOSITED INDIUM TIN OXIDE-FILMS AS TRANSPARENT CONDUCTORS AND COUNTERELECTRODES IN ELECTROCHROMIC SYSTEMS

Indium tin oxide (ITO) films sputter deposited near room temperature are studied for their application both as counterelectrodes and as transparent conductors in electrochromic (EC) systems. The optical and electrical changes in these films are studied as a function of lithium insertion using a dry method. These films exhibit a passive coloration in the solar and visible spectral ranges while improving their electronic conductivity with lithiation. Using the lithiation study results, a complete EC system with amorphous tungsten oxide EC layer and LiClO4 in propylene carbonate electrolyte is fabricated. The EC performance of such systems is reported. Such a system is capable of giving a fairly high optical modulation in the visible and solar spectral regions and suggests the potential use of ITO films for a simplified EC system.