Evaluation of Structural and Optical Properties of Nanocrystalline Cubic Y <sub>2</sub> O <sub>3</sub> Phase Materials via Combustion Method Using Different Fuels
A. Saliha Marjuka, S. Balamurugan, S. A. Ashika, T. K. Sana Fathima
Abstract
In this work, we have carried out combustion synthesis of nanocrystalline Y 2 O 3 materials using hexamine, polyethylene glycol(200) (PEG(200)), and ethylene glycol (EG) as fuels. In addition, the impact of mechanical stirring of commercial Y 2 O 3 powder with various dilutions of PEG(200) with distilled water as a solvent was also examined. The as-prepared combustion product of the hexamine is significantly different from other fuels (PEG(200) and EG). The annealed combustion products crystallize in the pure cubic Y 2 O 3 phase. The combustion product of PEG(200) reveals a maximum weight loss of ∼46% at 800 °C in the TG curve. The UV–vis-NIR features of different samples show quite interesting results. The E g values obtained from the Tauc plots are found in the range of 5.48 to 5.71 eV for the different samples. The observed strong FTIR band at 560 ∼ 415 cm −1 is owing to the vibrational Y–O bond in the present series samples. The Raman spectra show the highest intensity peak at wavenumber 374 cm −1 is owing to the F g vibrational mode of the Y 2 O 3 phase. Agglomerated nature of nanoparticles is seen in the Y 2 O 3 phase samples obtained from EG and hexamine as fuels. The PEG-derived Y 2 O 3 nanomaterials exhibit rather a high reflectance in the NIR region quite comparable to the NIR tendency of the mechanically stirred Y 2 O 3 samples. Thus, the present processed nanocrystalline Y 2 O 3 materials are efficient for solar reflective pigment application in the NIR industry.