Piezocatalysis Dye Degradation Using SrO-Bi₂O₃-B₂O₃ Glass-Ceramics

Abstract

SrO-Bi2O3-B2O3 (SBBO) transparent glasses were fabricated via the conventional melt quenching technique. X-ray diffraction (XRD) was carried out to confirm the glassy nature. Differential scanning calorimetry (DSC) was utilized to gain knowledge about the crystallization temperature, and following that glass samples were heat-treated to achieve crystallinity. The obtained values of the glass transition temperature (T g), the onset of crystallization temperature (T cr), and the peak crystallization (T p) temperature are 408, 438, and 440 °C, respectively. The glasses were heated at 440 °C for 30 min, 1 h, and 2 h to form glass-ceramics. The SrBi2B2O7 phase was formed during 1 h of heat treatment of the glasses. Studies of active vibration modes were done by Raman spectroscopy for SBBO glass and glass-ceramic samples. Piezocatalysis experiments were carried out for the removal of organic pollutants with Methylene Blue (MB) dye as a model dye, and the obtained maximum dye degradation was 51% with a kinetic rate of 0.002 min–1 under 240 min of ultrasonication. Experiments were repeated for 5 cycles to confirm the repeatability, and different dyes were used for degradation to confirm the reliability of the prepared glass-ceramic sample. Furthermore, Vigna radiata seeds were used to study the byproduct of dye that had been degraded for the assessment of phytotoxicity.

Effect of Poling and Porosity on BaTiO3 for Piezocatalytic Dye Degradation

“…These materials are able to convert mechanical energy into electrical energy via the direct piezoelectric effect 4,5 . Since these materials exhibit a high efficiency for energy conversion, the processes of piezocatalysis has emerged that uses the direct piezoelectric effect as an advanced oxidation process [6][7][8][9][10][11][12] . During piezocatalysis, or the piezo-electric-chemical coupling process, the charge generated under mechanical stimulation are separated and react with O2/OHto give rise to strong oxidizing active species, which are accountable for weakening organic contaminants [13][14][15] .…”