Metal hydride switchable mirrors (review)

At the end of the 20th century, the phenomenon of optical properties changing from mirror metal to transparent upon hydrogenation of thin films of some chromogenic materials was discovered. Such devices were called “switchable mirror.” The amazing properties of the new materials and the possibility of creating smart windows on their basis have caused an explosive growth in the number of their studies. However, insufficient light transmission in the transparent state and accelerated degradation of mirrors during cyclic switching quickly extinguished interest in them and sharply reduced the intensity of their development. Persistent 20-year research in improving the optical properties and durability of gas- and electrochromic switchable mirrors has allowed bringing these devices to a level close to practical application. An analysis and generalization of the results of the development of gas- and electrochromic switchable mirrors and an assessment of the prospects of commercial implementation of smart windows based on them have been presented.