Spectroelectrochemical studies of electrochromic diarylethene ionic Liquids: From solution to ionogel based devices

This study establishes the photoelectrochromic properties of four diarylethene ionic liquids (DAE-ILs) composed of a diarylethene dicarboxylate (DAE) moiety, as counter-anion, and different organic cations ([C10mim]+, [C16Pyr] +, [N8,8,8,1]+, [P6,6,6,14]+). The synthetized ILs viscous fluids maintain the photochemical and electrochemical properties of this well-known family of photoswitches, as well as the typical features of ILs (e.g., low melting point, and high thermal and electrochemical stability). Our strategy of making multi-stimuli-responsive ionic liquids by ionic exchange opens the door to easily tune the physicochemical properties of smart DAE-ILs in function of the selected cation. Finally, those DAE-ILs are used to formulate smart ionogels (IGs), a type of materials that, by showing good conductive properties and retaining the stimuli-responsive behavior of the embedded DAE molecules, allow the fabrication of photoelectrochemical devices.