Sol–gel derived organic–inorganic hybrid electrolytes for thin film electrochromic devices

Sol–gel derived, lithium ion conducting organic–inorganic hybrid electrolytes for ambient temperatures applications, have been synthesized from tetraethyl orthosilicate (TEOS), poly(ethylene oxide) (PEO), propylene carbonate (PC), propylene oxide, butyl acrylate, butyl methacrylate, ethyl acetoacetate and LiClO4 precursors. Mass fractions of the organic additions in the gels were of ca 30 mass% for gels 0/B, F–H and 40 mass% for gel J. The colorless transparent or translucent hybrid materials obtained in this work were aged at room temperature for at least three weeks and then dried at 80 °C for 3 h. The morphology and structure of all compositions were investigated by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM/EDX), Fourier transform infrared spectroscopy and 29Si MAS nuclear magnetic resonance. Amorphous nature of the hybrids was confirmed by X-ray diffraction. SEM, FTIR and NMR analysis showed structural properties and [SiO4] tetrahedrons poly-condensation process to be strongly influenced by organic additives have been employed. Room temperature ionic conductivities of the hybrid electrolytes were in a range of 9.84 × 10−4–1.56 × 10−3 Ω−1 cm−1.