Results and discussions Fig xA

Fig. 2 provides the FTIR spectra of the precursor and the Y2O3 powders calcined at different temperatures. A broad band at 3700–2800 cm−1 corresponds to WEHI-539 hydrochloride stretching vibration of OH−, and a band at 1635 cm−1 (partly overlapped by a broad band at 1520 cm−1) corresponds to HOH bend. Two bands at 1520 cm−1 and 1425 cm−1 correspond to the ν3 asymmetric and symmetric stretches of CO32−.