A Review on the Progress of Electrochromic Materials and Smart Device Technology

Materials that swap their color in response to stimuli are known as chromic materials, and among such, chromic materials that switch chromaticity in response to electric stimuli, called electrochromic (EC) materials, are more beneficial due to the consistency in the stimuli. The performance of the EC materials is determined by their electrochromic contrast, coloration efficiency, response time to change color or reverse back to its original color, optical memory and cyclic stability. EC materials can be organic or inorganic; however, organic materials' synthetic diversity and processability have acquired more attention and led to the development of many organic electrochromes.The organic EC systems can be basically classified into cathodically and anodically coloring systems, apart from these, the EC materials can be multicoloring and change its color from transmissive to black or black to transmissive systems. EC devices can be fabricated by various device structure consisting of transparent and conducting electrodes along with electrolytes. EC materials are widely employed in various commercial applications like smart windows, displays, camouflage applications, rearview mirrors, eye protective glasses, wearable electronics, and so forth. This review outlines the recent advancements in electrochromism, highlighting key developments, innovations, and trends.