Anhydrous proton-conducting imidazole triflate-SiO₂ composite

ImidazoleTriflate (ITF)-SiO₂ composites xITF-(100-x)SiO₂ were prepared by planetary ball-milling method. The structure of the composites was studied by TG-DTA, XRD and FT-IR methods. The ionic conductivity was assessed by alternative current (AC) electrochemical impedance measurement. From XRD results, the crystal size of imidazole triflate became smaller as its loading in xITF-(100-x)SiO₂ decreased. With x = 40 weight percent, the calculated crystal size was about 7.3 nm. FT-IR spectra showed the existence of CF₃SO₃ ^-···H⁺ ion aggregates and imidazole-proton bonds. The electrical conductivity of sample x = 50 was about 6.3 × 10^-3 Scm^-1 at 130 °C under anhydrous condition and about 30 times higher than that of sample x = 100.