Piezotronic Effect Induced Schottky Barrier Decrease to Boost the Plasmonic Charge Separation of BaTiO₃-Au Heterojunction for the Photocatalytic Selective Oxidation of Aminobenzyl Alcohol

Abstract

Charge carrier transfer efficiency as a crucial factor determines the performance of heterogeneous photocatalysis. Here, we demonstrate a simple nanohybrid structure of BaTiO3-Au (BTO-Au) for the efficient selective oxidization of benzyl alcohol to benzaldehyde upon piezotronic effect boosted plasmonic photocharge carrier transfer. With the aid of ultrasonic mechanical vibration, the reaction rate of the photocatalytic organic conversion would be considerably accelerated, which is about 4.2 and 6.2 times higher than those driven by sole visible light irradiation and sole ultrasonication, respectively. Photoelectrochemical tests under ultrasonic stimuli reveal the BTO-Au catalytic system is independent of the light intensity, showing a consistent photocurrent density, over a wide range of incident light brightness. The largely enhanced photocatalytic activity can be ascribed to the synergetic effect of surface plasmonic resonance (SPR)–piezotronic coupling by which a built-in electric field induced by the piezotronic effect significantly favors the oriented mobilization of energetic charge carriers generated by the SPR effect at the heterojunction. Notably, a decrease of the Schottky barrier height of ∼0.3 eV at the BTO-Au interface is verified experimentally, due to the band bending of BTO induced by the piezotronic effect, which can greatly augment the hot electron transfer efficiency. This work highlights the coupling of the piezotronic effect with SPR within the BTO-Au nanostructure as a versatile and promising route for efficient charge transfer in photocatalytic organic conversion.

Plasmon-induced hot carrier dynamics and utilization

“…The same group also determines the role of ultrasonication in improving the photocatalytic activity of a Au∕BaTiO 3 heterostructure. The Schottky barrier height is verified experimentally to be lowered by ∼0.3 eV [279] . Zhu et al used FTA spectroscopy to study the photodynamics of a Au NP/GaN film heterostructure where GaN is a piezoelectric semiconductor [280] .…”

Emerging Advancements in Piezoelectric Nanomaterials for Dynamic Tumor Therapy

“…Under strain, the displacement of Ti atoms from the central position of the TiO 6 octahedron induces the spontaneous polarization of BTO (p 0 ), as shown in Figure 4 a [ 36 ]. The piezoelectric response can be characterized by the hysteresis loop and butterfly curve by piezo−response force microscopy (PFM) ( Figure 4 b), and the piezoelectric field distribution can be simulated and imaged using finite element analysis ( Figure 4 c) [ 37 ]. The BTO with tetragonal crystal structure (T−BTO) features the strongest piezoelectric performance than other crystalline forms [ 38 ].…”

“…( c ) Finite element analysis of the electric field of BTO nanocubes at pressure of 100 MPa. Reproduced with permission [ 37 ]. Copyright 2022, American Chemical Society.…”

BaTiO3 Nanorod-Conjugated Silica Gel for Ultrasonic Water Purification via Piezocatalytic Generation of Reactive Oxygen Species

“…The resultant ROS then offer the degradation activity. Current research in this direction focuses on the preparation of materials with a high piezoelectric coefficient, [3][4][5]11,20 transformations of these materials into useful 2D/3D platforms, 9,12,15 and investigation of the piezocatalytic water purification performance. 12,15 We have recently demonstrated TiO 2 -templated BaTiO 3 nanorods with high piezocatalytic performance.…”