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Despite its considerable potential to address energy and environmental challenges, the practical application of photocatalysis is restricted by the limited efficiency of the photocatalysts. This research aims to improve the photocatalytic efficiency of Bi2MoO6 by adjusting the internal electric field within the crystal lattice via Te doping. Te-Bi2MoO6 nanosheets were prepared by a one-step hydrothermal method. Although the band gap energy and the long-range crystal structure are not affected upon doping, Te substitution provides several benefits to the performance of Bi2MoO6. First, the introduction of Te significantly reduces the thickness of the nanosheets, resulting in a larger surface area. Te states are also introduced into the conduction band, thereby increasing the carrier mobility. More importantly, the reduced cell parameters upon doping and the presence of Te in the lattice not only increase the potential difference between Bi–O and Mo-(Te)–O layers in the lattice but also create an asymmetric potential difference. As a result, an internal electric field is enlarged, leading to increased carrier separation. Consequently, 5.0 mol % Te-doped Bi2MoO6 could degrade 99.7% of Rhodamine B in 1 h under visible light, with 6.4 times higher rate constant than pristine Bi2MoO6. Additionally, the doped sample also exhibits about two times enhancement in benzylamine photooxidation (85% conversion vs 39% conversion) while maintaining excellent stability. Thus, this research highlights the efficacy of modulating the internal electric field through chemical modification as a viable strategy for enhancing the performance of photocatalysts. [ABSTRACT FROM AUTHOR]

Coating of photocatalytic nanomaterials on various surfaces enables interesting applications. This work demonstrates the ability of the aerosol-assisted chemical vapor deposition (AACVD) approach to prepare high-quality BiOCl nanostructure-based films and also to tune the nanostructure and photocatalytic properties of the films by varying the solvent and carrier gas. Solvents have a dramatic impact on the surface morphologies and crystallite size. X-ray diffraction (XRD) and grazing incidence X-ray diffraction (GIXRD) analyses indicate that BiOCl crystals displayed preferential growth in the (101) plane in most samples, while both the (101) and (102) planes were favored in films deposited using ethyl acetate and methanol. Surface energy and adsorption energy calculation reveal that the preferred growth depends on the interaction between the Bi atom and solvent molecules. X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDS) characterizations showed that all films did not contain any impurity elements but did contain some oxygen vacancies. The obtained nanostructured BiOCl films show good photocatalytic properties. The highest photocatalytic NOx removal efficiency is achieved in the film prepared using ethyl acetate and air, which we attribute to the large crystallite size and therefore high mobility of the carriers. Herein, we show that different crystal morphologies and sizes of BiOCl have strong impacts on the photocatalytic activity toward NO oxidation, and both factors can be effectively tuned in the AACVD process. Such knowledge may be useful for future research on coating materials for resolving environmental problems. [ABSTRACT FROM AUTHOR]