Enhanced photocatalytic performance of Au nanoparticles-modified rose flower-like Bi₂WO₆ hierarchical architectures

Abstract

Rose flower-like Bi 2 WO 6 hierarchical architectures with average diameter of 7¯m were synthesized via a hydrothermal route. The as-synthesized Bi 2 WO 6 hierarchical architectures were decorated with Au nanoparticles (20110 nm in size) by a photocatalytic reduction method. The prepared samples were systematically investigated by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, ultravioletvisible diffuse reflectance spectroscopy, electrochemical impedance spectroscopy and photocurrent response. The photocatalytic performance of the samples was evaluated by the degradation of RhB in aqueous solution under simulated sunlight irradiation. It is observed that AuBi 2 WO 6 composite exhibits a photocatalytic activity much higher (about 2.7 times higher) than that of bare Bi 2 WO 6 . The enhanced photocatalytic activity of AuBi 2 WO 6 can be attributed to the enhanced separation of photogenerated electronhole pairs due to the electron migration from Bi 2 WO 6 hierarchical architectures to Au nanoparticles. As a result, more electrons and holes are able to participate in the photocatalytic reactions. The underlying photocatalytic mechanism was discussed.

Enhanced Photocatalytic Performance and Mechanism of Au@CaTiO3 Composites with Au Nanoparticles Assembled on CaTiO3 Nanocuboids

“…Au NPs cannot be excited under UV irradiation, but they can act as excellent electron sinks to capture the photogenerated electrons in CaTiO 3 . This is because the Fermi level of Au (+0.45 V vs. normal hydrogen electrode (NHE) [71,72]) is more positive than the CB potential of CaTiO 3 (−0.43 V vs. NHE [55]). The electron transfer process from the CB of CaTiO 3 to Au NPs promotes the spatial separation of the electron/hole pairs in CaTiO 3 .…”

Recent Progress in Photocatalytic Degradation of Water Pollution by Bismuth Tungstate

“…These categories are summarized in Table 1. For example, in Figure 4, Guo et al [57] and Zheng et al [58] achieved knob-like and rose-like morphologies of Bi 2 WO 6 photocatalytic materials using the hydrothermal method. Wang et al [59] obtained a Bi 2 WO 6 photocatalytic material consisting of nanosheets with a large specific surface area through hydrothermal synthesis.…”

“…Figure 4. SEM images of (A) knob-like[57], (B) rose-like[58], (C) nanosheets[59], and (D) powder[60] Bi2WO6 catalyst.…”

Au and Co3O4 anchored Bi2WO6 with enhanced electron paramagnetic resonance, surface plasmon resonance, nonlinear and magnetic properties

“…The highly disordered structure composed of O 2p and Bi 6s hybrid orbitals of aurivillius-phase perovskite Bi 2 WO 6 (BWO) has endowed it with narrow band gap energy (2.6-2.9 eV), promising linear and nonlinear and magnetic performance. [1][2][3] The nonuniform charge distribution between layers of BWO may induce an internal electric field, resulting in high polarization.…”