Synthesis, characterization, optoelectronic and photocatalytic properties of Sr2Bi2O5/SrCO3 and Sr3Bi2O6/SrCO3 heterostructures with varying SrCO3 content

Dmitry S Shtarev; Anna V Shtareva; Ruslan Kevorkyants; Alexander V Syuy

doi:10.1016/j.chemosphere.2020.129229

Synthesis, characterization, optoelectronic and photocatalytic properties of Sr₂Bi₂O₅/SrCO₃ and Sr₃Bi₂O₆/SrCO₃ heterostructures with varying SrCO₃ content

Chemosphere. 2021 Mar:267:129229. doi: 10.1016/j.chemosphere.2020.129229. Epub 2020 Dec 5.

Authors

Dmitry S Shtarev¹, Anna V Shtareva², Ruslan Kevorkyants³, Alexander V Syuy⁴

Affiliations

¹ Yu. A. Kosygin Institute of Tectonics and Geophysics, Far Eastern Branch of the Russian Academy of Sciences, 65 Kim Yu Chen Street, Khabarovsk, 680000, Russia; Far Eastern State Transport University, 47 Seryshev Street, Khabarovsk, 680021, Russia. Electronic address: shtarev@mail.ru.
² Yu. A. Kosygin Institute of Tectonics and Geophysics, Far Eastern Branch of the Russian Academy of Sciences, 65 Kim Yu Chen Street, Khabarovsk, 680000, Russia.
³ St. Petersburg State University, Laboratory "Photoactive Nanocomposite Materials", Ulyanovskaya 1, St. Petersburg, 198504, Russia.
⁴ Moscow Institute of Physics and Technology, Department of General and Applied Physics, Institutskiy per. 9, Dolgoprudny, 141701, Russia.

PMID: 33333382
DOI: 10.1016/j.chemosphere.2020.129229

Abstract

We report on the structure and properties of novel Sr₂Bi₂O₅/SrCO₃ and Sr₃Bi₂O₆/SrCO₃ heterostructures with SrCO₃ content varying from 10 wt% to 90 wt%. Formation of the heterostructures is succeeded via sintering technique and according to XRD, SEM, and EDX studies has resulted in highly crystalline materials with well-defined carbonate-bismuthate interfaces. In the reaction of photodegradation of phenol in aqueous solution the heterostructures demonstrated photocatalytic activity exceeding that of TiO₂. It is demonstrated that their photocatalytic action is due to the presence of type II semiconductor heterojunctions. The content of SrCO₃ ensuring utmost photocatalytic activity is explained based on numerical modeling of the heterostructures' formation using 'Unity' development platform. In addition, the heterostructures show photoluminescence. Its mechanism proposed here implies permeability of the materials' heterojunctions to electrons. This work describes new materials that can be used for photodegradation of organic pollutants. Besides, it extends available principles of design of photocatalytically active heterostructures.

Keywords: DFT calculations; Heterostructures; Luminescence; Visible light photocatalysts.

MeSH terms

Catalysis
Phenol*
Photolysis

Substances

Phenol