VANADIUM PENTOXIDE GELS

Vanadium pentoxide gels have been known for more than a century. Fifty years ago they were used as models to study the hydrodynamic behavior of rodlike colloidal particles. Interest in them was renewed a decade ago by the discovery of their semiconducting properties and their use as antistatic coatings in the photographic industry. Since then vanadium pentoxide gels have been extensively studied by "sol-gel" scientists. They have a layered structure and give rise to anisotropic coatings when deposited onto a substrate. Such coatings exhibit a wide variety of electronic, ionic, and electrochemical properties. They behave as versatile host structures for the intercalation of ionic and molecular species and can be used for making humidity sensors, microbatteries, electrochromic display devices, and optical memories.