A Novel Molybdotungstosilicate Gel Electrolyte with Wide Electrochemical Stability Window

New hybrid gel electrolyte [MIMPS](4)SiW11MoO40 (IL-SiW11Mo) has been synthesized from the heteropoly acid H4SiW11MoO40 and 1-(3-sulfonic group) propyl-3-methyl imidazolium (abbreviated as MIMPS). The results of FTIR and XRD reveal that the synthesized polyoxometalate-based gel electrolyte possesses lamellar structure and exhibits the characteristic thermo-tropic liquid-crystalline behavior, which can undergo a phase transformation from a viscous gel state to liquid state below 100 degrees C. Its ionic conductivity of up to similar to 10(-3) S cm(-1) was observed above the phase transformation temperature. The electrochemical stability potential window (ESW) of IL-SiW11Mo was found to be about 4V at room temperature. The electrochemical impedance spectroscopy (EIS) was carried out to study the capacitance and ion mobility of IL-POM used as electrolyte. The results show that IL-SiW11Mo has high capacitance and fast ion mobility.