Electrochromic Properties of Electrospun Fibers Based on Bis-Thiomethylcyclohexanone Derivatives

In this work, the electrochromic (EC) application of the hybrid fibers based on bis-thiomethylcyclohexanone derivatives is evaluated. For this purpose, two new bis-thiomethylcyclohexanone derivatives, 2,6-bis(phenyl(phenylthio)methyl) cyclohexanone (PPTMC) and 2,6-bis((2,6-dichlorophenyl)(phenylthio)methyl)cyclohexanone (CPPTMC), were synthesized by thio-Michael addition and characterized by spectroscopic methods and X-ray diffraction. The hybrid fibers based on bisthiomethylcyclohexanone and poly(methyl methacrylate) (PMMA) were successfully prepared with electrospinning. The surface morphology and elemental compositions of these hybrid fibers were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The electrochemical, optical and electrochromic behaviors of indium tin oxide (ITO) glass substrates coated with those fibers were evaluated using spectrophotometry techniques. Moreover, the electrochromic devices (ECDs) based on PPTMC-PMMA and CPPTMC-PMMA hybrid fibers showed reversible color change from the transparent state to light brown by switching from +3.0 to -3.0 V. The calculated coloration efficiency of the hybrid fibers based on PPTMC-PMMA was found to be 207.27 cm(2)/C whereas a higher coloration efficiency was obtained for the hybrid fibers based on CPPTMC-PMMA (273.31 cm(2)/C). Our results show that hybrid fibers based on PPTMC-PMMA and CPPTMC-PMMA are potential materials for optical and electrochromic applications.