Multi‐stimuli‐responsive and Multi‐functional Smart Windows

Smart windows can change their optical characteristics according to environmental conditions or external stimuli (such as heat and electricity). They are manufactured by considering building characteristics, regional climate, energy policies, and indoor air conditions. Their key optical properties have been improved by developing novel materials, fabrication methods, and designs. The optical properties can be further improved by developing multi‐stimuli‐responsive smart window systems. Recently, some smart windows have been integrated with energy storage, solar energy harvesting, self‐cleaning, and air‐purifying functions. The energy consumed by buildings and houses accounts for a considerable portion of the total energy consumed by a country as well as the world; therefore, these state‐of‐the‐art smart windows will greatly contribute to saving energy. Moreover, some multi‐functional smart windows can help in addressing environmental challenges. This mini‐review particularly focuses on discussing the recent advances made in multi‐stimuli‐responsive and multi‐functional smart windows, in addition to summarizing the researches on electrochromic, thermochromic, and other types of smart windows. Smart windows switch colors and optical transmittance according to stimuli or changes in environmental conditions. Their key performances can be improved by responding to more than two stimuli. Additionally, the smart windows can have energy storage, light energy harvest, self‐cleaning, and indoor air purification functions. The minireview focuses on these multi‐stimuli‐responsive and multi‐functional smart windows that can contribute to saving building energy costs and maintaining clean indoor air.