Monolithic gels of silica and nonionic surfactant: Matrices for the dispersion of metal ions
Tóm tắt
The formation of homogeneous monolithic gels by the addition of TEOS to acidic amphiphilic solutions has been investigated for a range of nonionic surfactants, and the relationships between solution composition and gelation examined. Using the surfactant solutions as a means of pre-doping the matrices with high concentrations of manganese nitrate gave gels which could be calcined to 400°C with little or no segregation of manganese oxide observed by X-ray diffraction. X-ray absorption spectroscopy has shown that the ligand environment of manganese in the silica-surfactant matrices differs from that in gels derived from ethanol solutions, and that most of the manganese in the calcined gels remains in a disordered environment.
Tài liệu tham khảo
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