Figure 5
From: Morphology and Photoluminescence of HfO2Obtained by Microwave-Hydrothermal
a UV–vis absorbance spectra of rice-like HfO2nanostructures obtained by MH at 140 °C for 1 h. Inset illustrates a wide band model composed of intermediary levels within the band gap as well as the indirect electronic transition process.b PL spectrum at room temperature of rice-like HfO2nanostructures. Inset shows the different bond angles between the O–H–O bonds for the [HfO6] clusters