Preparation and Performance of High-Proton Conductive Silica Gels Containing Molybdotungstovanadogermanic Heteropoly Acid

• Published in: Journal of solid state chemistry Vol. 148; no. 2; pp. 419 - 424
• Main Authors: Wu, Qingyin, Lin, Haohao, Meng, Guangyao
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.12.1999; Elsevier
• Subjects: Chemistry; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Infrared spectrometry; Heteropolyacid; Scanning electron microscopy; Sol gel process; Preparation; Doping; Thermogravimetry; Proton conductivity; Differential thermal analysis; Silica gel; X ray diffraction; Modified material
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1006/jssc.1999.8470

The silica gel containing molybdotungstovanadogermanic acid was prepared by means of the sol–gel method. SEM and infrared spectra revealed that the Keggin structure characteristic of the GeW9Mo2VO5−40 anion was presented in the silica gel skeleton. The regularity of the change of characteristic peaks in the infrared spectra was investigated. The XRD pattern of the gel was amorphous. The TG curve showed three steps of weight loss. The DTA curve showed that the thermal stability of the gel is lower than that of the pure molybdotungstovanadogermanic acid. The gel exhibited considerably high proton conductivity, which increased with the increase of the molybdotungstovanadogermanic acid content. The proton conductivity of the gel containing 71 wt% molybdotungstovanadogermanic acid is 1.86×10−3 S cm−1 at 18°C.