Crystals (Apr 2022)

Crystallization of Glasses Containing K<sub>2</sub>O, PbO, BaO, Al<sub>2</sub>O<sub>3</sub>, B<sub>2</sub>O<sub>3</sub>, and TiO<sub>2</sub>

  • Patricia Ponce-Peña,
  • María Azucena González-Lozano,
  • Miguel Ángel Escobedo-Bretado,
  • Diola Marina Núñez-Ramírez,
  • Alicia Rodríguez-Pulido,
  • Zoe V. Quiñones Jurado,
  • Martha Poisot,
  • Belkis Sulbarán-Rangel

DOI
https://doi.org/10.3390/cryst12050574
Journal volume & issue
Vol. 12, no. 5
p. 574

Abstract

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The objective of this work was to obtain glass-ceramics from stable glasses, with a composition of barium, lead, and potassium titanate phases, for use as semiconductors. For this purpose, the glass-ceramic technique was used to control crystal growth and obtain a fine-grained microstructure. Various glasses containing K2O, PbO, BaO, Al2O3, B2O3, and TiO2 were prepared using a melt-quenching method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) showed a single amorphous phase of all samples. Infrared spectra confirmed the presence of B-O bonds stretching vibrations of (B3O6)3− boroxol rings and BO3 triangles, as well as Ti-O stretching vibrations of (TiO6/2) and (AlO6/2) octahedral units. Thermal analyses confirmed the presence of one or more crystallization peaks in the range of 700 to 744 °C. On this base, they were heat-treated to promote crystal growth. XRD and SEM detected Ba4Ti12O27, Ti7O13, and BaTiO3 phases, homogeneously distributed throughout the material with fine crystallite size. In addition, crystallized glasses’ (glass-ceramics) properties were determined; the density values were 2.8–3.55 g/cm3; the chemical resistance to acidic and basic media was low; and the band-gap values were in the range of 2.88 to 3.05 eV. These results suggest that crystallized glasses may have application in photocatalysis.

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