Dynamic Internal Field Engineering in BaTiO₃-TiO₂ Nanostructures for Photocatalytic Dye Degradation

Abstract

Ferroelectric-semiconductor nanostructures can exhibit enhanced photocatalytic activity benefiting from charge separation and transport facilitated by a spontaneous polarization-induced electric field. However, this static electric field can be easily compensated, thus hindering enhancement of photocatalysis. In this study, we propose to introduce a consecutive periodic thermal variation into BaTiO3-TiO2 nanostructures to achieve excellent photocatalysis via dynamic internal field engineering based on the pyroelectric effect of BaTiO3. The theoretical simulation reveals that spontaneous polarization of BaTiO3 can be changed with temperature, which in consequence varies strength and distribution of the polarization-induced electric field, leading to the formation of a dynamic internal field in the BaTiO3-TiO2 nanostructures. Experimental evidence proved that the dynamic internal field facilitated by the consecutive thermal variation can function for incessant charge separation and transport as well as accelerated catalytic reactions over the BaTiO3-TiO2 nanostructures, thereby resulting in significantly improved degradation efficiency with a remarkable cyclic ability.

Nanohybrids of Layered Titanate and Bismuth Vanadate as Visible-Light-Driven Photocatalysts for the Degradation of Dyes and Antibiotic

“…During the past few decades, researchers have explored a variety of inorganic materials for visible-light-driven active photocatalysis. Most visible-light photocatalysts suffer from low efficiency, high exciton recombination, poor photostability, and inappropriate band positions to reduce protons and oxidize oxide ions. , Consequently, attempts were made to enhance the photocatalytic activity by doping, nanostructuring photocatalysts, and hybridization with wide-band gap semiconductors. Nanostructure hybridization with intimate electronic coupling can enable effective electron–hole pair separation, thus improving the photocatalytic activity of semiconducting materials .…”

Managing the surface piezoelectricity effect of the smart ZnO sandwich nanoplates using metal foam core layer and GPRL reinforced rim layers

“…Nanostructuring has been found to enhance properties like thermal shock resistance by reducing thermal conductivity, thereby protecting samples during thermal shocks [32,33]. Furthermore, manipulating nanostructure internal fields through thermal variations can improve catalytic reactions and degradation efficiency [34]. Studies have also shown that prestress fields can dramatically alter nanostructure phonon properties and thermal conductivity [35].…”

Piezo-Phototronic Coupling Effect in CuBi2O4/AgNbO3 Z-Scheme Heterojunction for High-Efficiency Decomposition of Organic Dye

“…Moreover, the depolarization electric field originating from the spontaneous polarization of ferroelectrics and the piezoelectric potential generated under stress in ferro-/piezoelectric materials with the piezoelectric effect are also used as the built-in electric field to suppress the recombination of photoinduced carriers in the photocatalyst. Ferroelectric materials with the depolarization electric field and piezoelectric potential have been widely used to boost photocatalytic efficiency. − AgNbO 3 as an antiferroelectric material with a piezoelectric coefficient of 330 pC/N exhibits a stronger piezoelectric response, and enhances the photocatalytic performances of AgNbO 3 by regulating its ferro-/piezoelectric characteristics has been proved to be an important strategy. − However, the limited visible light absorption ability of AgNbO 3 with a wider band gap (∼2.8 eV) hinders further improvement of its photocatalytic degradation performance. Constructing AgNbO 3 and the semiconductor with a narrower band gap to be a heterojunction is a simple and effective strategy to enhance its visible light absorption ability, and this heterojunction photocatalyst with suitable energy band matching is expected to achieve enhanced carrier separation ability.…”