Remediation Of Organic Pollutants Research Articles

Immobilization of MnO2 nanoflowers on coils using direct heating method for organic pollutant remediation

The immobilization of catalysts on supporting substrates for the removal of organic pollutants is a crucial strategy for mitigating catalyst loss during wastewater treatment. This study presented a rapid and cost-effective direct heating method for synthesizing MnO2 nanoflowers on coil substrates for the removal of organic pollutants. Traditional methods often require high power, expensive equipment, and long synthesis times. In contrast, the direct heating approach successfully synthesized MnO2 nanoflowers in just 10 min with a heating power of approximately 40 W·h after the heating power and duration were optimized. These nanoflowers effectively degraded 99% Rhodamine B in 60 min with consistent repeatability. The catalytic mechanisms are attributed to crystal defects in MnO2, which generate electrons to produce H2O2. Mn2+ ions in the acidic solution further dissociate H2O2 molecules into hydroxyl radicals (·OH). The high efficiency of this synthesis method and the excellent reusability of MnO2 nanoflowers highlight their potential as a promising solution for the development of supporting MnO2 catalysts for organic dye removal applications.

Advancement in Photocatalyst and Piezophotocatalyst Micromotor for Environmental Remediation: A Concise Review

This review analyses recent advancements in the synthesis and environmental applications of photocatalysts and piezophotocatalysts, pivotal for organic pollutant degradation and water remediation. Traditional semiconductor photocatalysts often face rapid electron-hole recombination and limited visible light absorption. Innovations have led to the development of semiconductor heterojunctions that enhance photocatalytic efficiency by improving charge separation and expanding light absorption. This review emphasizes semiconductor-semiconductor and semiconductor-metal interfaces, which significantly improve photocatalytic performance. Additionally, piezophotocatalysts have emerged, utilizing mechanical energy to augment chemical reactions, thereby increasing efficiency and applicability under various conditions. The review also highlights the role of photocatalyst-based microrobots in targeted water treatment, utilizing local chemical energy for precise operations. These advancements showcase the potential of photocatalytic and piezophotocatalytic technologies in environmental sustainability, highlighting current trends and future prospects for effective environmental remediation.

A review on algae-mediated adsorption and catalytic processes for organic water pollution remediation

Wastewaters consist of organic pollutants that have environmental concerns. Wastewaters are treated by different methods, but efficient, low-cost, and sustainable techniques still need to be developed. Algae-based water pollution remediation techniques are considered to be sustainable approaches. This review exclusively discusses the facets of macro and microalgae in the treatment of organic toxicants. The current trends of algae-mediated water treatments have been discussed under adsorption and degradation methods. A focus on algae fuel cell, algae mediated activation of oxidizing agents, Fenton-like reactions, and photocatalysis was given. The need of algae-based adsorptive and catalytic materials was mentioned. The role of algae in the synthesis of catalysts which were employed in pollutant removal methods was also explained. The integrated algae-mediated water treatment techniques were also highlighted. The toxicant removal performances of different algae-based materials in the water medium were summarized. The conclusion and future prospects derived from the literature survey were described. This review will be helpful for researchers who are working in the field of sustainable water pollution remediation.

Eco-friendly plant extract-assisted fabrication of CeO2@CH@Ag nanocomposite: A heterogeneous catalyst for organic pollutant remediation

This study explores the synthesis and application of a novel cerium oxide-chitosan-silver (CeO2@CH@Ag) nanocomposite as an efficient catalyst for the reduction of organic pollutants, including methyl orange (MO), congo red (CR), and 4-nitroaniline (4-NA). The nanocomposite was synthesized via a co-precipitation method, followed by in-situ deposition of silver nanoparticles on its surface. Comprehensive characterization techniques, including FTIR, XRD, FESEM, EDX, XPS and nitrogen sorption measurements, confirmed the successful incorporation of CeO₂ and silver within the chitosan matrix. The CeO2@CH@Ag nanocatalyst exhibited a high surface area of 58.081 m2/g, exhibiting remarkable catalytic activity, facilitating rapid reduction of the organic pollutants within 6 min using sodium borohydride as a reducing agent. Kinetic studies revealed pseudo-first-order reaction kinetics, with rate constants of 1.09, 0.38, and 0.58 min⁻1 for MO, CR, and 4-NA, respectively. The proposed mechanism involves the adsorption of dye molecules onto the catalyst's porous surface, followed by electron transfer from the reducing agent to the dye, facilitated by the redox properties of CeO2 and silver. The CeO2@CH@Ag nanocatalyst demonstrates the promising potential for efficient wastewater treatment and remediation of organic pollutants.

Bismuth molybdate nanoparticles modified graphene oxide: A novel nanocomposite for photocatalytic removal of organic dyes

Utilization of solar energy for the degradation of organic pollutants is a promising sustainable approach. Here in this research work, bismuth molybdate (Bi2MoO6) nanoparticles (NPs) modified graphene oxide sheets (Bi2MoO6@GO) were employed as efficient photocatalysts for the removal of organic dyes under illuminated sunlight. The synthesized nanocomposite was subjected to characterization via XRD, FTIR, Raman, SEM, EDX and UV–Vis spectroscopic analysis. The photocatalytic efficiency of fabricated nanocomposite (Bi2MoO6@GO) has been studied against organic pollutants including rhodamine B and methylene blue in aqueous solution under direct sunlight irradiation. Bi2MoO6 decorated graphene oxide nano-photocatalyst exhibited 91 % and 88 % degradation of methylene blue and rhodamine B within ∼ 70 min with apparent rate constant values of 0.0323 and 0.0246 min−1, respectively. The study showed that fabricated photocatalyst (Bi2MoO6@GO) possesses a comparatively low band gap, heterogeneous morphology and boosted active surface area which makes it an efficient photocatalyst for the effective remediation of organic pollutants.

Enhancing hydrochar production and proprieties from biogenic waste: Merging response surface methodology and machine learning for organic pollutant remediation

The valorization of biogenic waste by hydrothermal carbonization is widely discussed in research. However, to our knowledge, no study has combined almond shells and olive pomace to synthesize a solid carbon material. The purpose of this study is to enhance the hydrochar process from AS and OP using RSM methodology and machine learning models: ANN, SVM and XG-Boost. Subsequently, a study was carried out on the removal of organic pollutants by the synthesized material. The optimum Co-HTC operating conditions obtained at 180 C, 90 min with acid catalyst corresponding to 71.51 % and 87.13 % for mass yield and carbon retention rate respectively according to RSM-CCD. The comparison between RSM-CCD and ML in terms of prediction concludes that RSM remains more efficient in terms of planning and optimization. However, ANN is more suitable for modeling and predicting mass yields and carbon retention rates. Hydrochar’s physicochemical properties were evaluated by the use of spectroscopic methods like FTIR, SEM, XRD, and CHNO. To conclude, we studied the performance of HCop in methylene blue adsorption, varying the following parameters: pH, contact time, initial dye concentration, adsorbent dose and temperature. In addition, kinetic and isothermal models were studied to describe the dominant mechanisms in the MB adsorption process. The MB maximal adsorption using HCop obtained at pH 9, with an initial dye concentration of 100 mg. L−1, 40-min contact time, 0.1 g/L adsorbent dose, and a temperature between 25 and 30 °C. In conclusion, these results provide important information on the use of Co-HTC to convert biogenic wastes into high-performance carbon materials for the appropriate removal of organic pollutants. More studies are needed to use the material in other fields of application.

The influence of vermicompost on atrazine microbial degradation performance and pathway in black soil, Northeast China

The atrazine (ATR) is extensively used in dryland crops like corn and sorghum in black soil region of Northeast China, posing ecological risks due to toxic metabolites. Vermicompost are known for soil organic pollution remediation but their role in pesticide degradation in black soil remains understudied. The influence of vermicompost on the microbial degradation pathway of atrazine was assessed in this study. Although vermicompost didn't significantly boost atrazine removal, they notably aided in primary metabolite degradation, hydroxyatrazine (HYA), deisopropylatrazine (DIA), and deethylatrazine (DEA), reducing their content by 38.67 %. They also altered the soil microbial community structure, favoring atrazine-degrading bacteria like Proteobacteria, Firmicutes, and Actinobacteria. Five secondary degradation products were identified in vermicompost treatments. Atrazine degradation occurred via dechlorination, dealkylation, and deamination pathways mainly by Nocardioidacea, Streptomycetaceae, Bacillaceae, Sphingomonadaceae, Comamonadaceae and Nitrososphaeraceae. pH and available nitrogen (AN) influenced microbial community structure and atrazine degradation, correlating with vermicompost application rates. Future black soil remediation should optimize application rates based on atrazine content and soil properties.

Reactive complexes mediated singlet oxygen production by MnO2 catalyzed peracetic acid: Characterization and DFT study

Advanced oxidation technology based on peracetic acid (PAA) has been a hot issue in the remediation of refractory organic pollutants. Here, we investigated manganese dioxide (α-MnO2) effectively activate the in-situ generated PAA by rapid perhydrolysis of sodium percarbonate (SPC) and tetraacetylethylenediamine (TAED) to degrade sulfamethoxazole (SMX). This system followed non-radical pathway only dominated by singlet oxygen (1O2), which can exhibit excellent anti-interference capacity. The generation of metastable manganese intermediates (Mn-PAA*) is a key step in the formation of 1O2. The formation of Mn-PAA* is confirmed by electrochemical and in-situ Raman tests. With the help of density functional theory (DFT), we have probed the behavior of PAA activation on different crystal planes to produce 1O2, with OH cleavage to generate MnIV−O-OOCCH3 being the decisive step for the formation of 1O2. This study is the first to investigate the mechanism of non-radical mediated PAA activation by α-MnO2 and in-depth research the role of Mn-PAA* in the 1O2 generation. The proposed new insights into non-radical process of PAA activation by transition metal will further advance the application of PAA-based AOPs.

Cellulose acetate sheet supported gold nanoparticles for the catalytic reduction of toxic organic pollutants

Abstract Water contamination by toxic organic dyes represents a significant global challenge necessitating effective remediation strategies. Due to their high catalytic activity, considerable attention has been gained to metal-based nanocatalysts. Cellulose acetate sheets supported by gold nanoparticles through a reduction method were synthesized. The composite synthesized material presents a compelling platform for catalytic reduction in the remediation of toxic organic pollutants, ensuring controlled particle size and stability. In this study, the prepared cellulose acetate sheet (CAsheet) was dipped in a 0.001 M aqueous chloroauric acid (HAuCl4) solution and reduced by immersion in a 0.1 M sodium borohydride (NaBH4) aqueous solution. After the successful preparation of virgin cellulose acetate sheet (CAsheet) and gold-supported cellulose acetate sheet (Au-CAsheet) samples were assessed by scanning electron microscopy (SEM), X-ray crystallography (XRD), energy dispersive X-rays spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR) analysis. The catalytic reduction reaction of toxic compounds i.e. reduction of 4-nitroaniline (4-NA), Congo red (CR), and reactive yellow (RY-42) by using NaBH4. The catalytic activity of the Au-CAsheet was exhibited by the reaction rate constant (k app) values 0.3189, 0.1596, and 0.1593 min−1 for CR, 4-NA, and RY-42 respectively. This kind of procedure for Au-CAsheet synthesis may be valid for different applications in catalysis, sensing, and environmental application.

Enhancing degradation of sulfamethoxazole by layered double hydroxide/carbon nanotubes catalyst via synergistic effect of photocatalysis/persulfate activation

A Co3Mn-LDHs and carbon nanotube (Co3Mn-LDHs/CNT) composite catalyst was constructed for permonosulfate (PMS) activation and degrading sulfamethoxazole (SMX) under Vis light irradiation. The introduction of CNTs into Co3Mn-LDHs facilitate the exciton dissociation and carrier migration, and the e− and h+ were readily separated from Co3Mn-LDHs/CNT in the photocatalysis process, which promoted the production rate of reactive oxygen species (ROS), so the Co3Mn-LDHs + Vis + PMS system exhibited better activity with an SMX degradation ratio of 61.25% than those of Co3Mn-LDHs + Vis system (42.30%) and Co3Mn-LDHs + PMS system (48.30%). After 10 cycles, the degradation rate of SMX only decreased by 7.16%, indicating the good reusability of the Co3Mn-LDHs/CNTs catalyst. The results of electron paramagnetic resonance (EPR) analysis and radical quenching experiments demonstrated that that the SO4•− played crucial role for SMX removal in Co3Mn-LDHs/CNTs + Vis + PMS system, and both e− and h+ made an important contribution to activating PMS to produce ROS. Overall, this work provided an excellent catalyst for photo-assisted PMS activation and suggested the activation mechanism for organic pollutant remediation.

Interfacial engineering and vacancy design of quasi-2D NiCoAl-LDH/Kaolin hybrid for activating peroxymonosulfate to boost degradation of antibiotics

Oxygen vacancies are prevalent in metal compounds and play a significant role in the activation of peroxomonosulfate (PMS) to mitigate water pollution. However, how to easily construct these oxygen vacancies and elucidate the mechanism of PMS activation by oxygen vacancies are still pending research and solution. This study presents the synthesis of a NiCoAl-LDH/Kaolin (NiCoAl-LDH/Kao) hybrid catalyst with quasi-2D layer structures morphology and abundant oxygen vacancies (OVs) for activating peroxymonosulfate (PMS). We proposed an intriguing phase transformation from NiCo-carbonate hydroxide (CH) to NiCoAl-layered double hydroxide (LDH), and elucidated the morphological evolution mechanism from nanorod to nanosheet structures through alkaline etching. The NiCoAl-LDH/Kao-PMS system exhibited excellent rapid kinetics and removal efficiency of norfloxacin (NOR), degrading 92.0 % of NOR within 10 min and achieving a final degradation rate of 97.2 %, along with remarkable reusability performance of the NiCoAl-LDH/Kao catalyst. Furthermore, reactive oxygen species including sulfate radical (SO4−), hydroxyl radical (OH), superoxide anion (O2−) and singlet oxygen (1O2) were found to be involved in the degradation process of NOR, and the degree of activity of the active groups from strong to weak is 1O2, SO4−, O2− and OH. The activation mechanism and conceivable degradation pathways of NOR were experimentally studied and proposed, and the toxicity of degradation intermediates was evaluated. The facile preparation method for NiCoAl-LDH/Kao nanocomposite holds potential for large-scale manufacturing in organic pollutant remediation, while also providing new insights on the indispensable role of OVs in heterogeneous catalysis.

A facile “one-pot” synthesized CaAl MnO4 LDH with a high loading capacity of oxidants for the sustained oxidation of oxytetracycline in soil

This study aims to address previous issues such as low payload of sustained release materials and excessive consumption of oxidants by developing novel sustained-release oxidation agents. Through a one-pot synthesis method, MnO4- intercalated Ca-Al-layered double hydroxide (CaAl MnO4 LDH) was synthesized with an oxidant payload of 4.82 mmol/g, constituting 53.2 % of the total mass. MnO4- exists in the sustained-release material in two forms: 57 % in free state and 43 % intercalated. The free MnO4- rapidly degrades oxytetracycline (OTC), while the intercalated MnO4- is gradually released from the LDH interlayers through ion exchange and interface dissolution, continuously degrading OTC desorbed from the soil. Additionally, CaAl LDH readily releases Ca2+; the small molecular acids and CO2 generated after OTC degradation will re-fix Ca2+ to form CaCO3, achieving carbon sequestration and enhancing the utilization efficiency of Ca2+. In simulated OTC contaminated soil columns (50 mg/kg) treated with 0.5 wt% MnO4 LDH at a water flow rate of 0.04 ml/min, it was confirmed that the oxidant utilization efficiency of MnO4 LDH was 3.5 times higher than that of the KMnO4 system, removing 99.8 % of OTC within 40 days. This study provides new insights for the design of sustained-release materials and theoretical support for the remediation of organic pollutants.

Machine learning (ML): An emerging tool to access the production and application of biochar in the treatment of contaminated water and wastewater

To achieve sustainable development goals (SDGs), drinking water and/or wastewater treatment must be performed at a minimum cost along with negligible environmental impacts. Traditional approaches, like coagulation, precipitation, ion exchange, and membrane filtration have numerous drawbacks in terms of cost and effectiveness. Recently, the thermochemical conversion of biomasses/lignocellulosic wastes for biochar production and subsequently their application in the remediation of contaminated matrices is gaining attention. Further, the application of machine learning (ML) and artificial intelligence (AI) to optimize the production and application of biochar is a topical topic. Therefore, this review critically explains the optimised production process of biochar and its application in the removal of a diverse range of organic and inorganic contaminants from contaminated water and wastewater. Moreover, the review highlights the progress in organic and inorganic pollutants remediation with biochar, focusing on the significance and benefits of utilizing ML and AI to optimize adsorption variables and biochar feedstock properties. The surface area, porosity, and functional groups of the biochar, the type and quantity of the pollutants and the solution's pH, temperature, and ionic strength, all influence the adsorption capacity of the biochar. Furthermore, the duration of the biochar's interaction with the contaminants and the existence of competing ions are significant factors. Utilizing AI and ML proves to be efficient in terms of cost and time, enabling a multidisciplinary approach to eliminate pollutants using biochar. Finally, this review discusses the challenges associated with the application of ML and AI in the treatment of contaminated water and wastewater using biochar and proposed future prospects to make these technologies economically viable and sustainable.

Nonthermal plasma processing catalyzed by CuFe2O4 for organic pollutants remediation and bacterial inactivation with density functional theory

The suggested nonthermal plasma has been employed for organic pollutants remediation and bacterial inactivation with catalyst (CuFe2O4) via reactive oxygen and nitrogen species, along with catalytic density functional theory processing. The plasma generated species O2− (g.), OH• (g.), H2O2 (aq.), and NOx (aq.) are used for the remediation of organic pollutants, such as reactive black5 and bromocresol green with catalytic oxidative and reductive transformation, like as from Fe2+ (aq.) to Fe3+ (aq.) and from Cu2+ (aq.) to Cu1+ (aq.), respectively. In the presence of plasma with CuFe2O4, the pollutants remediation enhanced more, which is 95 ± 0.78%, rather than only plasma. After removal of pollutants, the plasma processing catalyzed by CuFe2O4 was highly inactivated the E. coli. bacterial growth, which inhibition rate is 100 ± 0.87% and 100 ± 0.69% for reactive black5 and bromocresol green, rather than only plasma, such as 86.41 ± 0.91% and 73.91 ± 0.56%, respectively. The CuFe2O4 generated super oxides (O2− (aq.)) and hydroxides (H+(aq.), OH⦁(aq.), and OOH⦁(aq.)) are rapidly react with bacteria to damage the bacterial cell membrane via catalytic redox process. However, the plasma generated species were react with catalyst to produce the e− charge densities under the redox transformation of spin orientation (±) 0.58 e−, which is 0.007, 0.009, and 0.005 electrons per cubic Angstrom, for CuFe2O4, H2O2(aq.), and NOx(aq.). The plasma generated species concentrations were quantified in the deionized water, which are H2O2(aq.) (145 ± 0.91 μM) and NOx(aq.) (112 ± 0.56 μM), respectively. After eradication of pollutants, the water pH was observed, which is near to the neutral at 6.57 ± 0.27 under the catalytic binary redox process. Moreover, the catalytic stability examined via reusability test, which were four cycles for reactive black5 and three cycles for bromocresol green. Furthermore, the CuFe2O4 nanoparticles conducted several characterizations to analyze the various properties, such as crystal, surface, functional, and elemental.

H2O2-free catalytic dye degradation at dye/night circumstances using CuS@Au heterostructures decorating on MoS2 nanoflowers

Catalytic remediation of industrial organic pollutants is considered effective mitigation of increasing risks from aqueous contaminations composed of hazardous substances. The need for in-situ environmental remediation is highly demanded to deal with organic contaminations from on-site, instant, and full-time treatment without the need to remove the contaminated sources for ex-situ remediation is highly demanded. In this work, by means of combining the strategies of daytime and dark degradation capabilities of organic dyes, the MoS2/Au@CuS hybrid catalysts resembling semiconductor/metal/semiconductor junction features underline the generation of hydroxyl radicals, and force to speed up the oxidative removal of organic dyes during light-on and light-off conditions in both scenarios. Decorations of CuS on hydrothermally synthesized MoS2/Au nanoflowers are prepared with the in-situ chemical reduction process. We reveal that such circumstance exists when programming the environment in the sequence of light-on/light-off conditions, which actively clicks the generation of H2O2 and strategically accelerates the degradation kinetics, offering an additional opportunity for promoting catalytic degradation of hazardous organic dyes with whole-day feasibility.

Recent Advances in Porous Bio-Polymer Composites for the Remediation of Organic Pollutants.

The increasing awareness of the importance of a clean and sustainable environment, coupled with the rapid growth of both population and technology, has instilled in people a strong inclination to address the issue of wastewater treatment. This global concern has prompted individuals to prioritize the proper management and purification of wastewater. Organic pollutants are very persistent and due to their destructive effects, it is necessary to remove them from wastewater. In the last decade, porous organic polymers (POPs) have garnered interest among researchers due to their effectiveness in removing various types of pollutants. Porous biopolymers seem to be suitable candidates among POPs. Sustainable consumption and environmental protection, as well as reducing the consumption of toxic chemicals, are the advantages of using biopolymers in the preparation of effective composites to remove pollutants. Composites containing porous biopolymers, like other POPs, can remove various pollutants through absorption, membrane filtration, or oxidative and photocatalytic effects. Although composites based on porous biopolymers shown relatively good performance in removing pollutants, their insufficient strength limits their performance. On the other hand, in comparison with other POPs, including covalent organic frameworks, they have weaker performance. Therefore, porous organic biopolymers are generally used in composites with other compounds. Therefore, it seems necessary to research the performance of these composites and investigate the reasons for using composite components. This review exhaustively investigates the recent progress in the use of composites containing porous biopolymers in the removal of organic pollutants in the form of adsorbents, membranes, catalysts, etc. Information regarding the mechanism, composite functionality, and the reasons for using each component in the construction of composites are discussed. The following provides a vision of future opportunities for the preparation of porous composites from biopolymers.

Graphene-based photocatalytic membrane application for the remediation of organic dye pollutants: A review

The inadequate elimination of emerging organic contaminants, such as pharmaceuticals and personal care items, presents a substantial risk to water security in treating wastewater and its subsequent discharge into the receiving water bodies or recharging groundwater. A practical solution can be found by combining hybrid photocatalytic oxidation with membrane separation technologies. The review examines the crucial process of strengthening photocatalytic membranes by including graphene and its derivatives. Further, it highlights the graphene's ability to improve anti-fouling properties with increased efficiency of pollutant degradation. An in-depth analysis of the synthesis method and its impact on graphene-based photocatalytic membranes' morphology and photocatalytic characteristics is conducted. In addition to discussing membrane alteration, the review delves into the different elements and complexities involved in optimising filtration performance. Adding a comparison with carbon-based support membranes enhances the overall understating of graphene's importance in the membrane matrix. Economic and life cycle aspects have also been elaborated to gauge the practical viability of these neoteric photoactive membranes. The present article also pinpoints the existing lacuna and lays forward potential solutions that can assist in broader acceptance of these membrane for contaminant remediation. Though the development of graphene-based photocatalytic membranes is still in an embryonic phase, the review advocates it as a sustainable successor to conventional membrane-based treatment in the future.

Paracoccus benzoatiresistens sp. nov., a benzoate resistance and selenite reduction bacterium isolated from wetland.

A Gram-stain-negative, aerobic, non-motile, catalase- and oxidase-positive, pale orange, rod-shaped strain EF6T, was isolated from a natural wetland reserve in Hebei province, China. The strain grew at 25-37°C (optimum, 30°C), pH 5-9 (optimum, pH 7), and in the presence of 1.0-4.0% (w/v) NaCl (optimum, 2%). A phylogenetic analysis based on 16S rRNA gene sequence revealed that strain EF6T belongs to the genus Paracoccus, and the closest members were Paracoccus shandongensis wg2T with 98.1% similarity, Paracoccus fontiphilus MVW-1T (97.9%), Paracoccus everestensis S8-55T (97.7%), Paracoccus subflavus GY0581T (97.6%), Paracoccus sediminis CMB17T (97.3%), Paracoccus caeni MJ17T (97.0%), and Paracoccus angustae E6T (97.0%). The genome size of strain EF6T was 4.88Mb, and the DNA G + C content was 65.3%. The digital DNA-DNA hybridization, average nucleotide identity, and average amino acid identity values between strain EF6T and the reference strains were all below the threshold limit for species delineation (< 32.8%, < 88.0%, and < 86.7%, respectively). The major fatty acids (≥ 5.0%) were summed feature 8 (86.3%, C18:1 ω6c and/or C18:1 ω7c) and C18:1 (5.0%) and the only isoprenoid quinone was Q-10. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, two unidentified glycolipids, five unidentified phospholipids, and an unidentified aminolipid. Strain EF6T displays notable resistance to benzoate and selenite, with higher tolerance levels (25 g/L for benzoate and 150 mM for selenite) compared to the closely related species. Genomic analysis identified six benzoate resistance genes (acdA, pcaF, fadA, pcaC, purB, and catA) and twenty selenite resistance and reduction-related genes (iscR, ssuB, ssuD, selA, selD and so on). Additionally, EF6T possesses unique genes (catA, ssuB, and ssuC) absent in the closely related species for benzoate and selenite resistance. Its robust resistance to benzoate and selenite, coupled with its genomic makeup, make EF6T a promising candidate for the remediation of both organic and inorganic pollutants. It is worth noting that the specific resistance phenotypes described above were not reported in other novel species in Paracoccus. Based on the results of biochemical, physiological, phylogenetic, and chemotaxonomic analyses, combined with comparisons of the 16S rRNA gene sequence and the whole genome sequence, strain EF6T is considered to represent a novel species of the genus Paracoccus within the family Rhodobacteraceae, for which the name Paracoccus benzoatiresistens sp. nov. is proposed. The type strain is EF6T (= GDMCC 1.3400T = JCM 35642T = MCCC 1K08702T).

Piezo-enhanced photocatalysis of MoS2/Bi4O5Br2/PVDF-HFP film for wastewater purification

To date, the piezoelectric field has been demonstrated as a promising approach to inhibit the recombination of photogenerated carrier in photocatalyst applications. Herein we propose a MoS2/Bi4O5Br2/PVDF-HFP piezo-photocatalytic film in the organic pollutants remediation. MoS2/Bi4O5Br2 as the photocatalytic material is incorporated to poly (vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP) as the supporting layer via a simple phase transition method. The polarised electric field generated on PVDF-HFP and MoS2/Bi4O5Br2 under aeration synergised with the built-in electric field formed between MoS2/Bi4O5Br2 Z-scheme heterojunction to promote the interfacial charge transfer. The degradation rates of rhodamine B (RhB) and tetracycline hydrochloride (TC) under aeration and visible light irradiation in 60 min reached 98.9% and 92.2%, respectively. Meanwhile, density functional theory calculations (DFT) further demonstrated the effective charge separation and transfer induced by the Z-scheme charge transfer mechanism constructed by MoS2 composite with Bi4O5Br2, as well as the synergistic effect of the double electric field in favour of suppressing carrier recombination. This work provides an interesting solution for effectively combining piezoelectric catalysis with photocatalysis.

Fabricating of Pd and Ni bimetal modified halloysite nanotube composite and its application for photocatalytic degradation of tetracycline

Tetracycline (TC) is extensively employed as a broad-spectrum antibacterial agent, and its byproducts have been identified in a variety of water bodies, posing a significant risk to both aquatic ecosystems and human health. Among the prevalent techniques for treating water contaminants, photodegradation stands out. In this research, we synthesized a novel nanocomposite material, embedding bimetallic nanoparticles onto halloysite nanotubes (HNT) (Pd@Ni/N-HNT), aimed at photocatalytically degrading TC. The Pd@Ni/N-HNT demonstrated the capability to enhance the TC degradation efficiency to 100 % under visible light for a duration of 120 min, effectively doubling the performance of pure H2O2 degradation. The influence of pH levels in aquatic environments on the TC degradation efficiency was explored. Through electron spin resonance (EPR) studies and free radical scavenging tests, it was verified that •O2− and h+ are pivotal in the degradation process. Furthermore, Pd@Ni/N-HNT showcased effective degradation capabilities in both tap and river water, achieving degradation rates exceeding 70 % in 120 min and 95 % in 180 min, respectively. This investigation not only sheds light on the potential of utilizing Pd@Ni/N-HNT as a potent catalyst for the photocatalytic degradation of TC but also offers a comprehensive framework for the future development of nanomaterials aimed at the environmental remediation of organic pollutants. The findings herein provide a pivotal reference and guide for advancing the application of nanotechnology in the purification of water, thereby contributing to the safeguarding of aquatic ecosystems and public health.