Effect of surface/bulk polarization on piezocatalysis using BaTiO₃

BaTiO3 (BT) was synthesized using a solid-state reaction route. X-ray diffraction, Raman spectroscopy, and X-ray photoemission spectroscopy were conducted for structural analysis. The morphology of the prepared BT was analyzed with Scanning Electron Microscopy. Samples were exposed to different types of poling techniques i.e., surface poling through flexoelectric-like effect, traditional DC poling, and pulse poling. Two distinct sets of experiments were conducted to assess the impact of these poling techniques on dye degradation through piezocatalysis. The BT exhibited flexoelectric-like behavior on the ceramic surfaces, resulting in a 75% degradation compared to a surface layer-removed sample, which showed 25% degradation. Re-annealing the surface layer removed BT samples and partially restored their activity. In another set of experiments, pulse-poled samples showed d33 of 65pC/N which is significant because of the time of poling at room temperature. Dye was degraded using control, unpoled BT, pulse poled BT, DC poled BT, and control experiments with obtained degradations of 20, 30, 45, and 65%, respectively. Note that the results of the first set of experiments for the flexoelectric effect and the second set of experiments for the poling effect are completely independent. These observations conclude that both flexoelectric-like effect and pulse poling can be utilized for piezocatalysis activity.