Cerium sulfophenyl phosphate, a novel inorgano-organic solid proton-conducting material

Cerium sulfophenyl phosphate (CeSPP), a novel inorgano-organic solid proton conductor, was synthesized from the reaction of m-sulfophenyl phosphonic acid and hydrated cerous nitrate. The synthesized CeSPP was characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis (TGA), scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The TGA results reveal that CeSPP has good thermal stability. The synthesized CeSPP exhibited considerable high-proton conductivity. The proton conductivity was about 0.13 S/cm at 150 °C under 100% relative humidity. The proton conductivity at 105 °C at different RH was also measured.