Enhanced macroscopic polarization in bismuth titanate nanosheets for efficient piezo-photocatalytic degradation of pollutants by Nd doping

Abstract

Recently, piezo-photocatalysis has attracted great scientific interest, in which a piezoelectric field promotes the separation of photogenerated electron-hole pairs, thereby significantly enhancing the photocatalytic efficiency of the material. In this study, Bi_4-xNd_xTi₃O₁₂ (x = 0, 0.5, 0.75, 1.0, xNd-BTO) nanosheets were fabricated through a hydrothermal technique and employed as piezo-photocatalysts to degrade Rhodamine B (RhB) and diclofenac sodium (DS). Across all samples, 0.75Nd-BTO exhibited the highest piezo-photocatalytic efficiency, achieving complete RhB degradation in just 25 min, with an apparent rate constant of 0.2151 min⁻¹. This activity was approximately 9.31 times greater than that of pristine BTO, surpassing the performance of most piezo-photocatalysts reported. The appropriate amount of Nd doping increases the specific surface area, optimizes energy band structure, as well as promotes the coupling of piezoelectric and photocatalytic effects, which contribute to the excellent piezo-photocatalytic activity of 0.75Nd-BTO. In this work, it is shown that doping with appropriate amounts of Nd³⁺ can significantly improve the piezo-photocatalytic performance of piezoelectrics, which provides a feasible way to design efficient piezo-photocatalysts in the future.