INFRARED-SPECTRA OF THE RUBIDIUM NITRATE ALUMINA COMPOSITES

Infrared (IR) spectra do not show changes for hydrated or deuterated R bNO3 samples, where no hydrogen (deuterated) bondings are formed. Howe ver, in the presence of the second Al2O3 Phase, a splitting band at th e high frequency, 1425 cm-1 and a large wavenumber shift from 1380 to 1135 cm-1 are observed for the upsilon3 mode in the hydrated and deute rated RbNO3-Al2O3 samples. These changes results from the coordination of H-NO3 and the isotopic effect of H-NO3 and D-NO3 bondings, This is otopic effect is very similar to that of the H-O and D-O bondings. Fro m the IR study, it is suggested that the proton conduction in these co mposite materials is dominated by an interfacial conduction mechanism.