Black-to-Transmissive poly(vinyltriphenylamine) allowing multicolor electrochromic display

The field of electrochromic materials has been the subject of extensive research, with a particular focus on the development of strategies for precise color tuning. To date, two principal routes of investigation have been pursued. The initial approach involves the synthesis of the electrochromic material with the desired color, employing chemical engineering to achieve the targeted color. The second approach involves utilizing the electrochromic material as a shutter, alternating between achromatic and black states, with the device color corresponding to that of the electrolyte when the polymer is in its achromatic states. In this study, we propose a novel approach that combines the two aforementioned technologies. This novel approach offers straightforward access to bi- and trichromatic devices. The electrochromic material utilized in this study is a conjugated polymer, poly (vinyltriphenylamine) (PVTPA), which exhibits three distinct colorimetric states depending on the applied potential: achromatic, ochre, and black. This study reports the synthesis of the monomer and the polymer, as well as the electro-optical characteristics of PVTPA. The easy integration of PVTPA into devices is demonstrated by the development of bi- and trichromatic displays using different colored membranes (white, turquoise, and orange). Additionally, the switching times and color coordinates of these displays are assessed. The combination of an easily accessible electrochromic polymer and the use of colored membranes provides easy access to trichromatic devices with multiple color options.