IN-SITU OBSERVATION OF SURFACE HYDROXYL GROUP ON LITHIUM CERAMICS AT HIGH-TEMPERATURE BY INFRARED-ABSORPTION SPECTROSCOPY

Hydroxyl groups on the surface of Li2O were studied by using a diffuse reflectance method with Fourier transform infrared spectroscopy at high temperature up to 833K under controlled D2O or D-2 partial pressure. Multiple peaks due to the stretching vibration of O-D were observed at 2748, 2717, 2660, 2620, 2540, 2520, 2490cm(-1) showing a different behavior with temperature or atmosphere. When D-2 was added to the sweep gas, peak intensity of 2660 and 2620cm(-1) decreased. This result indicates that the surface nature is influenced by oxygen potential. Assignment of observed peaks to the surface nature was also discussed.