Corona-poling enhanced photocatalytic degradation of methyl-violet and rhodamine B pollutants using ferroelectric nanoparticles

Abstract

In this study, the effect of DC corona poling on the photocatalytic degradation response of conventional ferroelectric BaTiO3 nanoparticles over the methyl-violet and rhodamine B dyes has been investigated systematically. The BaTiO3 (BT) nanoparticles were synthesized via modified sol-gel route. The synthesized BT nanoparticles were characterized by using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX), P-E hysteresis loop, impedance analyzer, photoluminescence spectroscopy and UV–vis spectroscopy. X-ray diffraction (XRD) and Raman spectroscopy confirmed the tetragonal phase of BT nanoparticles. The average particle size was found to be 130 ​nm as confirmed by SEM. The P-E hysteresis loop confirmed the ferroelectric nature of the sample and the Tc was observed nearly 130 ​°C as confirmed by dielectric study. The optical bandgap was found to be 3.74 ​eV and 3.49 ​eV for unpoled and poled samples, respectively. The degradation efficiency of the corona poled and unpoled BaTiO3 samples for the rhodamine dye solution was 45% and 25%, respectively, whereas it was 93% and 83% for methyl violet dye solution in 120 ​min under UV–vis light. The corona poling enhanced the alignment of electric dipoles in BaTiO3, which causes higher spatial charge separation, lowering the electron-hole recombination and hence improved the degradation efficiency.