Achieving a large contrast, low driving voltage, and high stability electrochromic device with a viologen chromophore

Abstract

An electrochromic device that utilizes <italic>N</italic>,<italic>N</italic>,<italic>N</italic>′,<italic>N</italic>′-tetramethyl-<italic>p</italic>-phenylenediamine and the viologen radical salt (VRS) exhibits an extremely low driving voltage of 0.4 V, high transmittance change (&gt;60% at 620 nm) and enhanced write–erase ability.