Abstract
The state of surface hydroxyl groups on commercial sub-micron high purity alpha alumina powders produced by two different processes, in-situ chemical vapor deposition (AA-04, AA-05, and AA-07, Sumitomo Chemical Co. Ltd) and hydrolysis of aluminum alkoxide (AKP-30, AKP-50 and AKP-3000, Sumitomo Chemical Co. Ltd) method are evaluated by Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy and Temperature Programmed Desorption Mass Spectrometry (TPDMS). DRIFT analyses conducted in a heated cell give spectral changes in adsorbed water and hydroxyl groups at different temperatures. Also TPDMS results give accurate quantity of desorbed molecules from unit surface area calculated from measured partial pressures. Spectral changes of DRIFT and TPD spectra reveal surface reaction during heating. Kinds and quantities of surface species are estimated. The effects of different manufacturing processes including different grades of powder on the surface states of alpha alumina powder are discussed.
