Infrared Spectroscopy Studies of Aluminum Oxide and Metallic Aluminum Powders, Part I: Thermal Dehydration and Decomposition

In this work, we study three aluminum oxides (alpha, gamma, boehmite) and various oxidized metallic powders to observe their dehydration decomposition behavior using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) scanning electron microscopy (SEM). We find that a temperature increase the (aluminas) reduces physically adsorbed water molecules reveal presence of hydroxyl groups. All aluminas contained bridged hydroxyls located at 3670 cm?1; found additional surface hydroxyls, which varied based on oxidation state atom. Oxidized were aged resulted similar behavior; however, results differed depending method aging. naturally (NA-Al) with heavy form tri-hydroxide decomposed did not any detectable peaks. When artificial methods (AA-Al), both including 3670, 3700, 3730 cm?1, remaining boehmite-like surface. These show can be tailored for specific applications, regardless age. It also elucidates different ways pre-process control oxide layer, corroborated by comparison models studied herein.