Large-scale synthesis of porous Bi2O3 with oxygen vacancies for efficient photodegradation of methylene blue

Abstract

Photocatalytic degradation of organic pollutants has become a hot research topic because of its low energy consumption and environmental-friendly characteristics. Bismuth oxide (Bi2O3) nanocrystals with a bandgap ranging from 2.0 eV to 2.8 eV have attracted increasing attention due to high activity of photodegradation of organic pollutants by utilizing visible light. Though several methods have been developed to prepare Bi2O3-based semiconductor materials over recent years, it is still difficult to prepare highly active Bi2O3 catalysts in large scale with a simple method. Therefore, developing simple and feasible methods for the preparation of Bi2O3 nanocrystals in large scale is important for the potential applications in industrial wastewater treatment. In this work, we successfully prepared porous Bi2O3 in large scale via etching commercial BiSn powders, followed by thermal treatment with air. The acquired porous Bi2O3 exhibited excellent activity and stability in photocatalytic degradation of methylene blue. Further investigation of the mechanism witnessed that the suitable band structure of porous Bi2O3 allowed the generation of reactive oxygen species, such as O2−· and ·OH, which effectively degraded MB.

A Comprehensive Review on the Boosted Effects of Anion Vacancy in the Heterogeneous Photocatalytic Degradation, Part II: Focus on Oxygen Vacancy

“…The suitable band structure of porous Bi 2 O 3 generated • O 2 − and • OH reactive species toward MB photodegradation. 294 The surface-rich OV Bi/α-Bi 2 O 3 NPs loaded on g-C 3 N 4 nanosheets via a calcination− photoreduction technique (Bi/α-Bi 2 O 3 /g-C 3 N 4 , labeled as BBC) also showed a boosted visible light photocatalytic activity (TC, 90.2%; RhB, 95.6%) because of the synergistic effect of surface OVs and Bi NPs. 295 An oxygen-vacancy-rich MoS 2 /Bi 2 O 3 Z-scheme heterojunction catalyst (2-BO-MS) has been used for crystal violet photocatalytic degradation.…”

“…A large-scale porous Bi 2 O 3 has been prepared by Wang et al via etching commercial BiSn powders, followed by an air thermal treatment, and the sample has excellent stability in MB photocatalytic degradation process. The suitable band structure of porous Bi 2 O 3 generated • O 2 – and • OH reactive species toward MB photodegradation . The surface-rich OV Bi/α-Bi 2 O 3 NPs loaded on g-C 3 N 4 nanosheets via a calcination–photoreduction technique (Bi/α-Bi 2 O 3 /g-C 3 N 4 , labeled as BBC) also showed a boosted visible light photocatalytic activity (TC, 90.2%; RhB, 95.6%) because of the synergistic effect of surface OVs and Bi NPs …”

Boosting the Photocatalytic Performance of g-C3N4 through MoS2 Nanotubes with the Cavity Enhancement Effect

“…The rapid growth of the economy and society has resulted in an increase in energy consumption. Fossil fuels are the primary source of energy, and their demand has increased significantly, posing challenges due to their finite nature and the possibility of an energy crisis. − The consumption of fossil fuels is associated with the emission of greenhouse gases and industrial pollutants, leading to significant environmental pollution and degradation. − According to the annual report released by the National Oceanic and Atmospheric Administration (NOAA) of the United States, the global average CO 2 concentration is projected to reach 417.1 ppm in 2022, marking a 2.4 ppm increase from 2021. This upward trend exacerbates environmental challenges like global warming, serving as a poignant reminder of the urgent need for action. , To revolutionize the current situation, it is essential to explore sustainable and clean energy sources actively.…”

Heterojunctions of N-deficient g-C3N4/1T@2H-MoS2 with interfacial C–S–Mo coordination for enhanced photocatalytic activity

“…Various practical strategies have been developed, such as adsorption, ion exchange, membrane separation, and photocatalytic technology, to eliminate the residual organic matter in wastewater. 1–4 Owing to the green, environmentally friendly, and low-cost route, semiconductor-mediated photocatalysis under solar radiation is the most practical strategy, and it is extremely valuable in the degradation of organic pollutants. 5,6…”