Preparation and proton-conductibility of silica gel containing 64 wt.% undecatungstocobaltoaluminic heteropoly acid

Abstract

Silica gel containing 64 wt.% undecatungstocobaltoaluminic acid was prepared by means of sol–gel method. Scanning electron microscope (SEM) and infrared (IR) spectrum revealed that the Keggin structure characteristic of [Al(H 2O)CoW 11O 39] 7− anion was present in the silica gel skeleton. The change of the characteristic peaks in the infrared spectrum was investigated. Thermogravimetry (TG) curve shows that there are three steps of weight loss. Differential thermal analysis (DTA) curve shows that the thermal stability of the gel is lower than that of pure undecatungstocobaltoaluminic acid. The silica gel exhibits considerably high proton conductivity of 1.30×10 −3 S cm −1 at room temperature (14 °C).