Organic Electrochromic Materials: A Brief Review of Viologens, Phthalocyanines and Some Complexes of Transition Metals

An electrochromic material is one that has the ability to change its color reversibly to undergo redox reactions when stimulated by an electrical current or by an adequate potential difference. The electrochromic materials can be classified as transition metal oxides, intercalation materials or organic materials. This work has proposed to do a brief review of the class of organic electrochromic materials, giving greater emphasis to subclasses of viologens, phthalocyanines and transition metal complexes. These materials have a wide technological application, such as windows controllable transmittance (smart window) displays, rear-view mirrors for vehicles, among other applications.