Synthesizing BaTiO₃ Nanostructures to Explore Morphological Influence, Kinetics, and Mechanism of Piezocatalytic Dye Degradation

Abstract

Piezocatalysts have attracted much attention due to their excellent degradation ability for organics. In this work, three types of BaTiO 3 (BTO) nanostructures, including hydrothermally synthesized nanocubes (NCs), sol−gel calcined nanoparticles (NPs), and electrospun nanofibers (NFs), are prepared for catalyzing the dye degradation. Compared with the NCs and NPs, the NFs exhibit a higher piezocatalytic degradation performance due to the large specific surface area, fine crystal size, and easy deformation structure. Moreover, the kinetic factors, including initial dye concentration, ionic strength, ultrasonic power, and applied action, influencing the degradation performance of the BTO NFs are analyzed deeply. A high degradation rate constant of 0.0736 min −1 is achieved for rhodamine B, which is superior compared with the previous reports. The excellent stability of BTO NFs is demonstrated by the cycling tests, where a high degradation efficiency of 97.6% within 110 min is still obtained after the third cycle. Furthermore, the mechanism of piezocatalysis revealed that the hydroxyl and superoxide radicals are the main reactive species in the degradation process. This work is of importance for the development of high-performance piezocatalysts and highlights the potential of piezocatalysis for water remediation.

Piezocatalytic Foam for Highly Efficient Degradation of Aqueous Organics

“…This trend might be related to the reduction of the shielding effect of the adsorbed RhB molecules. [ 31,37 ] Also, the degradation ratio of RhB is negatively correlated with the volume of RhB solution, for the relatively less amount of piezocatalysts in solution (Figure S14, Supporting Information). Furthermore, to validate the degradation of RhB is a radical‐driven process; two reagents which dramatically affect the behavior of free radicals were added to the piezocatalytic reaction system for exploring their influence on piezocatalytic efficiency.…”

“…For example, nanoparticles with high aspect ratios could exhibit more deformation upon the same environmental perturbation. [ 36,37 ] In addition, the increase in the surface roughness of piezocatalysts could introduce more stress concentration as well as enlarge the contact area with reactants, which also boosts the piezocatalytic efficiency. [ 38 ] Representatively, Wu et al prepared transition metal dichalcogenides (TMDs) nanoflowers which could completely degrade rhodamine B (RhB) in water in 5 min under ultrasonic vibration, which is the highest piezocatalytic efficiency so far.…”

Piezocatalysis and Piezo‐Photocatalysis: Catalysts Classification and Modification Strategy, Reaction Mechanism, and Practical Application

“…[86] Nanoscaled perovskite titanates can be easily prepared via molten-salt, sol-gel and hydrothermal methods. For example, BaTiO 3 microdendrites, [45,87] (Ba,Sr)TiO 3 NWs, [77] BaTiO 3 nanofibers, [88,89] and Pb(Zr 0.52 Ti 0.48 )O 3 fibers [90] obtained by these methods demonstrated piezocatalytic activity toward water splitting and azo dyes degradation. Similarly, CH 3 NH 3 PbI 3 nanoparticles prepared by co-precipitation method have stronger polarization resulted from the larger displacement of Pb atom, which demonstrated excellent piezocatalytic H 2 generation performance.…”

Nonlinear Optical Thermometry—A Novel Temperature Sensing Strategy via Second Harmonic Generation (SHG) and Upconversion Luminescence in BaTiO3:Ho3+,Yb3+ Perovskite

“…[ 22–28 ] Titanate perovskites have received extensive attention, especially thanks to their splendid piezoelectric and emissive properties. [ 29,30 ] Barium titanate perovskite has a relatively low phonon energy (≈700 cm –1 ), favoring high UCL efficiency. [ 31 ] Noteworthy, as the high‐temperature phase of ABO 3 ‐type perovskite BaTiO 3 (cubic; Pmm, No.221) is cooled down from the high to room temperature, a non‐centrosymmetric structure is obtained, due to the fact that the center ion Ti 4+ and the oxygen octahedron (O 3 local symmetry) displace nonuniformly in respect to the corner ion Ba 2+ .…”