BaTiO3 Nanoparticles for highly efficient piezocatalytic reduction of toxic hexavalent chromium: Synthesis, optimization, and kinetic study

Abstract

Drinking water contamination with heavy metals from industrial activities is an important issue. In particular, the hexavalent chromium ions Cr (VI) which are classified as group (A) carcinogens. Our research reports an effective removal of hexavalent chromium from water through the use of BaTiO₃ (BTO) as a piezocatalyst. We meticulously prepared pure tetragonal BTO by optimizing the synthesis parameters. The optimized BTO catalyst was utilized for the removal of Cr(VI) under applied mechanical force and removed up to 96 % of Cr(VI) from the solution. Our kinetic study revealed that the reaction follows a pseudo-first order. Thermodynamic studies indicated that the reaction is most spontaneous at temperatures of 20 °C and concentrations of 20 ppm. Our proposed mechanism for removing Cr(VI) by BTO piezocatalysts suggests that only 15 % of chromium was removed by adsorption, while the rest was removed by reduction through the piezocatalytic process.