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Recently, there has been a notable rise in the prevalence of persistent pollutants in the environment, posing a significant hazard due to their toxicity and enduring nature. Conventional wastewater treatment methods employed in treatment plants rarely address these persistent pollutants adequately. Meanwhile, the concept of green synthesis has garnered considerable attention, owing to its environmentally friendly approach that utilizes fewer toxic chemicals and solvents. The utilization of materials derived from sustainable sources presents a promising avenue for solving pressing environmental concerns. Among the various sources of biological agents, plants stand out for their accessibility, eco-friendliness, and rich reserves of phytochemicals suitable for material synthesis. The plant extract-mediated synthesis of zinc oxide nanoparticles (ZnONPs) has emerged as a promising solution for applications in wastewater treatment. Thorough investigations into the factors influencing the properties of these green ZnONPs are essential to establish a detailed and reliable synthesis process. Major weaknesses inherent in ZnONPs can be addressed by changing the optical, magnetic, and interface properties through doping with various semiconductor materials. Consequently, research efforts to mitigate water pollution are being driven by both the future prospects and limitations of ZnO-based composites. This review underscores the recent advancements of plant extract-mediated ZnONP composites for water treatment., Competing Interests: Declarations. Ethics approval: Research does not involve any human participants and/or animals. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Clean water is an integral part of industries, agricultural activities and human life, but water contamination by toxic dyes, heavy metals, and oil spills is increasingly serious in the world. Aerogels with unique properties such as highly porous and extremely low density, tunable surface modification, excellent reusability, and thermal stability can contribute to addressing these issues. Thanks to high purity, biocompatibility and biodegradability, bacterial cellulose can be an ideal precursor source to produce aerogels. Here, we review the modification, regeneration, and applications of bacterial cellulose-based aerogels for water treatment. The modification of bacterial cellulose-based aerogels undergoes coating of hydrophobic agents, carbonization, and incorporation with other materials, e.g., ZIF-67, graphene oxide, nanoparticles, polyaniline. We emphasized features of modified aerogels on porosity, hydrophobicity, density, surface chemistry, and regeneration. Although major limits are relevant to the use of toxic coating agents, difficulty in bacterial culture, and production cost, the bacterial cellulose aerogels can obtain high performance for water treatment, particularly, catastrophic oil spills., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The global occurrence of textile dyes pollution has recently emerged, posing a serious threat to ecological systems. To abate dye contamination, we here developed a novel magnetic porous CoFe 2 O 4 @MIL-53(Al) nanocomposite by incorporating magnetic CoFe 2 O 4 nanoparticles with MIL-53(Al) metal-organic framework. This nanocomposite possessed a surface area of 197.144 m 2  g -1 and a pore volume of 0.413 cm 3  g -1 . The effect of contact time (5-120 min), concentration (5-50 mg L -1 ), dosage (0.1-1.0 g L -1 ), and pH (2-10) on Congo red adsorption was clarified. CoFe 2 O 4 @MIL-53(Al) could remove 95.85% of Cong red dye from water with an accelerated kinetic rate of 0.6544 min -1 within 10 min. The kinetic and isotherm models showed the predominance of Bangham and Temkin. According to Langmuir, the maximum uptake capacities of CoFe 2 O 4 @MIL-53(Al), CoFe 2 O 4 , and MIL-53(Al) adsorbents were 43.768, 17.982, and 15.295 mg g -1 , respectively. CoFe 2 O 4 @MIL-53(Al) was selected to optimize Cong red treatment using Box-Behnken experimental design. The outcomes showed that CoFe 2 O 4 @MIL-53(Al) achieved the highest experimental uptake capacity of 35.919 mg g -1 at concentration (29.966 mg L -1 ), time (14.926 min), and dosage (0.486 g L -1 ). CoFe 2 O 4 @MIL-53(Al) could treat dye mixture (methylene blue, methyl orange, Congo red, malachite green, and crystal violet) with an outstanding removal efficiency of 81.24% for 30 min, and could be reused up to five cycles. Therefore, novel recyclable and stable CoFe 2 O 4 @MIL-53(Al) is recommended to integrate well with real dye treatments systems., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Green synthesis of nanoparticles using plant extracts minimizes the usage of toxic chemicals or energy. Here, we concentrate on the green synthesis of nanoparticles using natural compounds from plant extracts and their applications in catalysis, water treatment and agriculture. Polyphenols, flavonoid, rutin, quercetin, myricetin, kaempferol, coumarin, and gallic acid in the plant extracts engage in the reduction and stabilization of green nanoparticles. Ten types of nanoparticles involving Ag, Au, Cu, Pt, CuO, ZnO, MgO, TiO 2 , Fe 3 O 4 , and ZrO 2 with emphasis on their formation mechanism are illuminated. We find that green nanoparticles serve as excellent, and recyclable catalysts for reduction of nitrophenols and synthesis of organic compounds with high yields of 83-100% and at least 5 recycles. Many emerging pollutants such as synthetic dyes, antibiotics, heavy metal and oils are effectively mitigated (90-100%) using green nanoparticles. In agriculture, green nanoparticles efficiently immobilize toxic compounds in soil. They are also sufficient nanopesticides to kill harmful larvae, and nanoinsecticides against dangerous vectors of pathogens. As potential nanofertilizers and nanoagrochemicals, green nanoparticles will open a revolution in green agriculture for sustainable development., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)