Pollution, including air pollution and water pollution, is related to the rapid development of industries, from which large amounts of various pollutants are released into the environment without proper treatment. Among the pollutants, organic pollutants are of particular concern because many organic compounds decompose at a very slow rate, so there is a high risk of accumulation in the environment before entering the human food chain.
There are many water treatment methods, such as coagulation, sintering, biodegradation, adsorption by activated carbon. However, these methods do not actually degrade organic contaminants, but instead transfer them to carriers, such as metal-organic frameworks, silica and activated carbon, or produce by-products such as highly toxic aromatic amines. Recently, advanced oxidation methods are promising to be developed to treat wastewater, especially textile and dyeing wastewater. This method usually uses catalysts that are semiconductors, which, under lighting conditions, generate HO radicals with very strong oxidizing ability, and can decompose most toxic organic substances.
Recognizing that, the collective of Department of Inorganic Materials, Institute of Materials Science, is making efforts to develop nanomaterial systems, nanostructured materials applied in environmental treatment and protection. In addition, the department's research is aimed at taking advantage of the department's strengths in using rare earth elements in its research. Since the beginning of 2022, the collective has published 05 articles in SCI and SCIE journals on the decomposition of toxic organic substances in the water environment, on the treatment of arsenite and phosphate pollution, on the treatment of CO emissions and many other high-quality studies.
Research results show that organic pollutants such as methyl blue, rhodamine B decompose better under visible light than in the presence of rare earth elements such as Ce-ZnO, Ta-ZnO, C/Ce codoped-ZnO supported on graphene. Besides, the mechanism of decomposition of organic matter by these materials is also fully studied (Figure 1).
Figure 1: Organic decomposition mechanism of materials a) C/Ce-ZnO@Gr, b) BiFeO3, c) Ce-ZnO
In addition, research conducted by the Department of Inorganic Materials also shows that the applications of rare earth elements are relatively diverse and effective. For example, nano-mixed oxides CeO2-Fe2O3 have the ability to oxidize CO gas to CO2 only at 270oC (Figure 2), La2O3 nanomaterials have phosphorus and arsenite adsorption capacity of 289.9 and 89.1 mg/g.
Figure 2. CO oxidation capacity of CeO2-Fe2O3 nanomaterials.
Some research results of the Department of Inorganic Materials on Synthesis of nanomaterials and nanostructured materials applied in treatment and environmental protection were published in journals such as:
● 2023. One-pot hydrothermal preparation of capsule-like nanocomposites of C/Ce-co-doped ZnO supported on graphene to enhance photodegradation. New Journal of Chemistry. https://doi.org/10.1039/D2NJ04937F, IF = 3.925 (Q1, Materials Chemistry)
● 2022. Kinetics and mechanism of photocatalytic degradation of rhodamine B on nanorod bismuth ferrite perovskite prepared by hydrothermal method. Research on Chemical Intermediates, pp.1-16. https://doi.org/10.1007/s11164-022-04877-5, IF = 3.134 (Q2, Chemistry)
● 2022. Synthesis of CeO2-Fe2O3 Mixed Oxides for Low-Temperature Carbon Monoxide Oxidation. Adsorption Science & Technology, 2022, https://doi.org/10.1155/2022/5945169, IF = 4.373 (Q2, Chemistry)
● 2022. A comparative study of 0D and 1D Ce-ZnO nanocatalysts on photocatalytic decomposition of organic pollutants", RSC advances, 11, no. 57: 36078-36088, DOI: 10.1039/D1RA07493H, IF = 4.036 (Q1, Chemical Engineering)
● 2022. La2O3 nanoparticles: synthesis and application for removal of arsenite and phosphate from water. Desalination and Water Treatment, 239 (2021): 259-269, https://doi.org/10.5004/dwt.2021.27818, IF = 1.273 (Q3, Water Science and Technology)
● 2023. One-step hydrothermal preparation of Ta-doped ZnO nanorods for improving decolorization efficiency under visible light. RSC advances, 13(8), pp.5208-5218. IF = 4.036 (Q1, Chemical Engineering)
● 2022. Structures and Reduction Kinetics of Pelletized Rich Iron Ores for Iron Production: a Case Study for Na Rua Iron Ore in Vietnam. Mining, Metallurgy & Exploration, 39(4), pp.1779-1792. IF = 1.695 (Q2, Metals and Alloys)
● 2023. Plastic waste in sandy beaches and surface water in Thanh Hoa, Vietnam: abundance, characterization, and sources. Environmental Monitoring and Assessment, 195(2), p.255. IF = 3.307 (Q2, Environmental Science)
● 2022. Heavy metals in surface sediments of the intertidal Thai Binh Coast, Gulf of Tonkin, East Sea, Vietnam: distribution, accumulation, and contamination assessment. Environmental Science and Pollution Research, pp.1-11. IF = 5.190 (Q2, Environmental Chemistry)
● 2022. Spatial distribution and baseline levels establishment of heavy metals in sediments along the Thai Binh coast, Vietnam. International Journal of Environmental Science and Technology, pp.1-8. IF = 3.519 (Q2, Environmental Engineering)
Translated by Tuyet Nhung
Link to Vietnamese version