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Published on: July 4, 2017
Effect of Pressure-Assisted Heat Treatment on the Crystalline Phase of Titanium Dioxide, Niobium Pentoxide, and
Pietra B Pires1, Maria E K Fuziki1, Giane G Lenzi1,2
1Departamento Acadêmico de Engenharia Química, Universidade Tecnológica Federal do Paraná, Campus Ponta Grossa, Ponta Grossa, Paraná 84017-220, Brazil.
Abstract:
Titanium dioxide, niobium pentoxide, and ruthenium-modified tungsten were synthesized using sol-gel methodology. The effect of pressure-assisted heat treatment (PAHT) on their structural, morphological, and optical properties was investigated. The X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, UV-vis diffuse reflectance spectroscopy, and Raman spectroscopy analyses highlighted significant changes in structural, morphological, and optical properties, especially in the phase, band gap energy, and visible light absorption after PAHT. The results indicated that the 100Ti:1Ru oxide, obtained by the sol-gel method, calcined at 800 °C, and subjected to PAHT, presented promising characteristics for chemical reactions activated by solar radiation, with a notable reduction in band gap and visible absorption. Furthermore, PAHT promoted more stable crystalline phases at temperatures much lower than those indicated in the literature related to synthesizing titanium dioxide and niobium pentoxide. These discoveries contribute significantly to the advancement of knowledge, providing valuable guidance for developing and optimizing materials with specific properties for technological applications.
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