News & Events

Michael G. Walter, Ph.D.

Posted on October 29, 2021


Date - October 29, 2021
1:00 pm - 2:00 pm


Associate Professor of Chemistry
Department of Chemistry
UNC Charlotte
Talk Title: Developing Photoactive Thiazolothiazole Materials for Electrofluorochromic and Voltage Sensing Applications


Thiazolothiazole (TTz) materials are promising molecular platforms for a variety of electronic and optical applications. We have developed TTz dye systems that can serve as an electrochromic material, as a dye for biosensing applications, and as a stable material for molecular electronics and energy storage. Extended TTz viologen structures demonstrate both reversible electrochromic behavior and high fluorescence quantum efficiency that is deactivated with electrochemical reduction. Water-soluble, chromogenic TTz derivatives show excellent reversibility and stable cycling in a simple aqueous, polyvinyl alcohol/borax gel electrolyte electrochromic device. They produce voltage-dependent purple or blue coloration and efficient electrofluorochromism. We have also developed environmentally sensitive asymmetric TTz derivatives can serve as molecular probes for cell imaging and cell membrane voltage sensing. These asymmetric TTz derivatives exhibit strong solvatofluorochromism with fluorescence quantum yields > 0.9. In vitro cell studies indicate good cell membrane localization, insignificant cytotoxicity, promising voltage sensitivities, and photostability that is 4 times higher than comparable dyes. Lastly, solution-processable TTz compounds can be used as charge transport layers in a variety of molecular electronic devices (OLEDs and OPVs) and as energy storage materials. Their ease of synthesis and purification, remarkable photophysical properties, and chemically sensitive TTz p-bridge make these materials attractive for multi-functional optoelectronic, electron transfer, electrochromic, and other photochemical / energy storage applications.