Surface hydration states of commercial high purity α-Al2O3 powders evaluated by temperature programmed desorption mass spectrometry and diffuse reflectance infrared Fourier transform spectroscopy

The presence of hydrogen bonded water molecules, amorphous Al(OH)3 and AlOOH structures, as well as associated and isolated hydroxyl groups on the surface of all the α-Al2O3 powders investigated is demonstrated. On the surface of one of the powders the presence of crystalline Al(OH)3 structures, as evidenced by an additional sharp peak in the H2O TPDMS spectrum, is confirmed.