Environmental Nanotechnology, Monitoring and Management最新文献

{"title":"Tracing potentially toxic elements and nutrient levels from extensive illegal mining using multivariate statistics, pollution indices and ecological assessments","authors":"Ebenezer Ebo Yahans Amuah ,&nbsp;Bernard Fei-Baffoe ,&nbsp;Lyndon Nii Adjiri Sackey ,&nbsp;Raymond Webrah Kazapoe ,&nbsp;Douti Biyogue Nang ,&nbsp;Paul Dankwa ,&nbsp;Benjamin Offei ,&nbsp;John Bentil","doi":"10.1016/j.enmm.2025.101043","DOIUrl":"10.1016/j.enmm.2025.101043","url":null,"abstract":"<div><div>Mining activities have increased the levels of Potentially Toxic Elements (PTEs) PTEs contamination in soils, leading to major concern due to their potential risk. This study considered pollution levels of PTEs and their possible implications in an illegal mining site in southern Ghana during the ban on small-scale mining activities. Soil samples were also collected from residential and pristine areas as controls. Individual, complex and multi-elemental indices and exposure assessment were the assessment computations used. As, Hg, Pb, Sr and V had a significant relationship (0.05, χ² (4) = 50.61, <em>p</em> &lt; 0.001). Multiple comparisons indicated substantial differences between the following variable pairs: Pb-As, Pb-Hg, As-Sr, As-V, Hg-Sr, and Hg-V. Nutrient levels were significantly differences (0.05, χ² (4) = 54.41, <em>p</em> &lt; 0.001) with significant differences between N-K, N-Zn, N-Na, P-K, P-Na, K-Zn, and Zn-Na. The Robust Compositional Contamination Index (RCCI) analysis showed that the area was heavily impacted following 85 % of the samples ranging between high and highest pollution. A comparative assessment revealed that all the pollution indices followed a similar trend of pristine &lt; residential &lt; mining site, except for Mn and Sr where a pattern pristine &gt; residential &gt; mining with an elemental trend: Mn &lt; V &lt; Sr &lt; Zn &lt; Cu &lt; As &lt; Pb &lt; Hg. The indirect and poor relations between EC and N (r = 0.19), P (r = 0.36), K (r = −0.58), Zn (r = 0.37), Na (r = −0.08) and Ca (r = −0.50) indicates that the mined site had a poor water-soluble capacity of plant uptake of some essential elements. Pollution levels follow a clear trend from pristine to residential to mining areas, with notable impacts on nutrient levels and plant uptake capacity. The analysis showed significant differences in elemental concentrations between illegally mined and pristine areas, with p-values of 0.001 for As, Cu, Hg, Mn, Pb, Sr, and Zn, and 0.003 for V, indicating that illegal mining has substantially elevated levels of these toxic metals. Immediate intervention and sustainable management are critical to address these environmental and ecological risks.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101043"},"PeriodicalIF":0.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ultrasound-assisted method to enhance rice husk ash adsorption characteristics for paracetamol removal","authors":"Letícia Reggiane de Carvalho Costa ,&nbsp;Keila Guerra Pacheco Nunes ,&nbsp;Vanessa Jurado-Davila ,&nbsp;Elvis Carissimi ,&nbsp;Liliana Amaral Féris","doi":"10.1016/j.enmm.2025.101045","DOIUrl":"10.1016/j.enmm.2025.101045","url":null,"abstract":"<div><div>The objective of this work was to evaluate the effect of modifying the rice husk ash particle surface using the ultrasonic technique. For this, a comparative analysis was performed on the paracetamol adsorption capacity using rice husk ash particles as adsorbents modified and non-modified by ultrasound-assisted method. Sorbent modification was carried out by exposing the rice husk ash to the ultrasound technique for a specified time (5, 15, 30 and 60 min). Also, it was characterized by surface area, pore diameter and volume, X-ray diffraction (XRD) and Fourier transform in infrared (FTIR). The adsorption parameters evaluated in batch-scale experiments were the contact time (0 to 60 min) and adsorbent concentration in solution (0 to 25 g.L^-1). The results obtained showed that the ultrasound modification made the particle less reactive, requiring a higher concentration of adsorbent (when compared to the unmodified solid) to obtain the same amount of model pollutant removal. The maximum paracetamol removal obtained in the tests with the original rice husk ash was 90 % after 30 min of contact and solid concentration of 13 g.L^-1. In the same contact time, for the rice husk ash modified in ultrasound, 20 g.L^-1 were needed, reaching 100 % removal of the pharmaceutical. This result demonstrates the functionalization of the technique and a good performance and application of the solid as an adsorbent for the removal of pharmaceutical compounds.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101045"},"PeriodicalIF":0.0,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial distribution and risk assessment of potentially toxic elements in coastal mangrove floodplain Top-Soils of Bangladesh","authors":"Rabeya Sultana ,&nbsp;Md. Riad Hossain ,&nbsp;Md Musfike Meraz ,&nbsp;Mehidi Ahmmed ,&nbsp;Shahidur R. Khan ,&nbsp;Tasrina Rabia Choudhury","doi":"10.1016/j.enmm.2025.101044","DOIUrl":"10.1016/j.enmm.2025.101044","url":null,"abstract":"<div><div>Soil pollution caused by human activity is becoming an increasingly urgent global concern. Floodplain soils are particularly susceptible to contamination due to their role as temporary sinks for sediments, nutrients, and pollutants transported by the river systems. Mangrove floodplains possess significant ecological value, being unique ecosystems that are especially vulnerable to pollution, particularly from potentially toxic elements (PTEs). This study provides a comprehensive analysis of the concentration and spatial distribution of PTEs in the soils of Koyra Upazila, Bangladesh, a region characterized by a coastal mangrove ecosystem. A total of 60 soil samples were collected from three subdivisions to assess pollution levels. The samples were subjected to acid digestion (65 % HNO3 and HClO4 in a 4:1 ratio) and were analyzed using Atomic Absorption Spectroscopy (AAS) with a varian system (Varian AA240 FS). The investigated PTEs, ranked by decreasing concentration, were Zn &gt; Cr &gt; Pb &gt; Ni &gt; Cd &gt; Hg. Zn exhibited the highest average concentration (67.15 ± 12.24 mg/kg), whereas Mercury had the lowest (0.02 ± 0.04 mg/kg). Distribution patterns, illustrated by Q-Q plots, revealed that Pb and Zn data closely followed a normal distribution, while Cd, Cr, and Hg displayed significant deviations, suggesting skewed distributions influenced by both natural variability and anthropogenic activities. Assessments using the Geo-accumulation Index (Igeo), Pollution Load Index (PLI), and Nemerow Integrated Pollution Index (NIPI) indicated that the soils were generally uncontaminated, although moderate pollution levels of Pb and Zn observed in specific locations. Potential Ecological Risk Index (PERI) analyses suggested minimal ecological risks, despite the moderate pollution levels revealed by PLI. Health risk assessments highlighted elevated non-carcinogenic and carcinogenic risks for children, particularly in the central and southern regions of the study area. Furthermore, a comparative analysis against international soil quality standards from Canada, the Netherlands, and Australia confirmed that the PTEs concentrations in the study area remained within permissible limits, indicating predominantly natural origins with minimal anthropogenic influence. The study establishes a critical baseline for PTEs concentration in the mangrove floodplain soils of Koyra Upazila, revealing localized risks, particularly in urban areas like Koyra union. While most PTE levels are within permissible limits, the findings highlight the need for periodic monitoring and targeted mitigation measures to protect vulnerable ecosystems and public health.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101044"},"PeriodicalIF":0.0,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of human health risk related with arsenic and other metal contamination in water of İznik lake (Turkey)","authors":"Şehnaz Şener ,&nbsp;Erhan Şener ,&nbsp;Cafer Bulut","doi":"10.1016/j.enmm.2025.101041","DOIUrl":"10.1016/j.enmm.2025.101041","url":null,"abstract":"<div><div>This comprehensive study examines the environmental dynamics of the İznik Lake which is the fifth largest natural lake of our country, investigating temporal and spatial trends in heavy metal pollution and its effects on human health. Lake water samples were taken from various areas of the lake (19 different sampling points), including the central area of the lake, surrounding areas, points where streams empty into the lake, and near the shoreline. The average concentrations (μg/L) of heavy metals were as follows: Al (13.66) &gt; Fe (11.37) &gt; As (6.15) &gt; Mn (2.54) &gt; Zn (2.46) &gt; Pb (0.61) &gt; Cu (0.42) &gt; Cr (0.36) &gt; Ni (0.22). Al, Fe and As are the metals found in the highest concentrations in lake waters. According to index results, water quality index (WQI) value and heavy metal pollution index (HPI) indicated suitable for use of waters as drinking water. All of the samples are in the “low pollution” class in accordance with the heavy metal evaluation index (HEI) and degree of contamination (Cdegree) values. In addition, HTL indicated “low toxicity” class. The results of the health risk assessments were that consumption of the lake water could lead to both carcinogenic and non-carcinogenic health problems in terms of As. The results indicate that İznik Lake is contaminated with heavy metals and is not suitable for drinking water or agricultural use. In addition, this study revealed that metals measured at low concentrations may have adverse effects on human health. This study for İznik Lake is one of the first in the field and can be a reference for future similar studies for the protection and safe use of the lake and control of pollutants around the lake.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101041"},"PeriodicalIF":0.0,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pinus radiata forest residue: A bio-adsorbent of choice for Cr (VI) removal from aqueous solution","authors":"Humberto Dax Bonilla Mancilla ,&nbsp;Jenny Del Pino Moreyra ,&nbsp;Juan José Bullon Rosas ,&nbsp;Alfredo Rubén Bernal Marcelo ,&nbsp;Candelaria Tejada Tovar ,&nbsp;Manoj Kumar Jindal ,&nbsp;Devendra Kumar ,&nbsp;Mika Sillanpää ,&nbsp;Djamel Ghernaout","doi":"10.1016/j.enmm.2025.101042","DOIUrl":"10.1016/j.enmm.2025.101042","url":null,"abstract":"<div><div>Hexavalent chromium (Cr(VI)) is a lethally harmful heavy metal that endangers human health and biodiversity worldwide. Conventional Cr(VI) removal procedures are frequently energy-consuming and also emit hazardous byproducts. The use of NaOH-activated <em>Pinus radiata</em> forest residue (PRFR) as a sustainable and adaptable adsorbent for the effective removal of Cr(VI) from aqueous solutions is demonstrated in this work. To validate the adsorption and adsorption mechanism, PRFR was characterized using FTIR (Fourier transform infrared spectroscopy), SEM (Scanning electron microscopy), and XRD (X-ray diffraction) methods. Batch experiment techniques were adopted to optimize the influences of initial concentration, pH, adsorbent dose, temperature, and contact duration for Cr(VI) adsorption, all of which are critical for use on an industrial or commercial scale. After 45 min of contact time, PRFR revealed a high adsorption capacity of 13.947 mg/g with a removal effectiveness of 99.12 % for Cr(VI). The adsorbent was reusable for more than three cycles. PRFR is a nature-friendly adsorbent that can be used for a variety of purposes, including wastewater treatment, industrial effluent remediation, and environmental restoration, because it is inexpensive and easily accessible.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101042"},"PeriodicalIF":0.0,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feedstock selection influences performance and mechanism of DNA adsorption onto biochar","authors":"Michael P. Schmidt ,&nbsp;Sierra Rupp ,&nbsp;Daniel J. Ashworth ,&nbsp;Duc Phan ,&nbsp;Ananda Bhattacharjee ,&nbsp;Jorge F.S. Ferreira ,&nbsp;Yujie Men ,&nbsp;Abasiofiok Mark Ibekwe","doi":"10.1016/j.enmm.2025.101040","DOIUrl":"10.1016/j.enmm.2025.101040","url":null,"abstract":"<div><div>Antibiotic-resistance genes (ARGs) in wastewater may promote antimicrobial resistance in consumers of crops irrigated with wastewater. Removal of DNA from wastewater may thus mitigate potential environmental risks associated with irrigation and environmental release of recycled wastewater. Although biochar adsorbents are a potentially cost-effective strategy for removing DNA from water, biochar feedstock influence on performance has not been studied across a range of feedstock classes. Our objective was to produce biochar from 5 distinct feedstocks (manure (MN), black mustard (<em>Brassica nigra</em>) (MU), orange peel (OP), pine pellet (PP) and macadamia nutshell (MNS)) at a fixed pyrolysis temperature (500 °C), characterize biochars and relate characteristics to DNA adsorption. Adsorption reached equilibrium within two hours and kinetics fit the pseudo-second order model. Adsorption rates increased from MNS, PP, OP, MN to MU, with rates of 3.06 × 10⁻², 5.65 × 10⁻², 1.78 × 10⁻¹, 4.00 × 10⁻¹ and 5.05 × 10⁻¹ mg g⁻¹ min⁻¹, respectively. Adsorption isotherms fit the Freundlich model, with affinities increasing from PP, MNS, OP, MN to MU (<em>K_d</em> = 1.30 × 10⁻², 1.35 × 10⁻², 1.27 × 10⁻¹, 1.96 × 10⁻¹ and 1.42, respectively). DNA adsorption on biochars increased with ionic strength from I = 0 – 0.10 M except for MN. Ca²⁺ addition increased adsorption for biochars at I = 0.01 and 0.10 M, except for MN, which increased only with I = 0.10 M. Lower sensitivity of adsorption on MN biochar to ionic conditions indicates a different mechanism may control adsorption. The high ash content of MN biochar may favor direct bonding of DNA to ash minerals compared to π-π interactions likely driving DNA adsorption to structural carbon. These findings help understand how feedstock-driven variability in biochars translates to DNA immobilization and will assist researchers and stakeholders in determining the most suitable feedstocks for this purpose.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101040"},"PeriodicalIF":0.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineered MnO2-Multiwalled carbon Nanotube nanoheterostructures for efficient removal of nanoplastics and plastic-derived contaminant Bisphenol S from contaminated water","authors":"Abhishek Mandal ,&nbsp;Arpan Sarkar ,&nbsp;Sangeetha Thykandi ,&nbsp;Soumadip Guchhait ,&nbsp;Gopala Krishna Darbha","doi":"10.1016/j.enmm.2024.101038","DOIUrl":"10.1016/j.enmm.2024.101038","url":null,"abstract":"<div><div>This study explores the potential application of engineered MnO₂-Multiwalled Carbon Nanotube (MWCNT) nanoheterostructures (NHs) for the simultaneous removal of nanoplastics (NPs) and bisphenol S (BPS) from polluted water, two persistent pollutants from plastic degradation that pose substantial health and ecological risks. The presence of ε-MnO₂ in the nanoheterostructure, confirmed by XRD, HRTEM, and XPS studies, enhances its surface reactivity due to microtwinning defects and mixed oxidation states of Mn. Under optimized conditions, MnO₂-MWCNT NHs achieved complete removal of 10 mg/L NPs and 1 ppm BPS at a dosage of 1.5 g/L within 24 h at 25 °C. The NP removal was facilitated by heteroaggregation with MnO₂-MWCNT NHs, following a pseudo-first-order kinetic model with a rate constant of 1.87 mg/L·min, achieving approximately 90 % removal within the first hour. BPS adsorption was an endothermic process, well-described by the Freundlich, Sips, and Dubinin–Astakhov (D-A) isotherm models, indicating an adsorption capacity exceeding 2 mg/g at 25 °C, primarily controlled by liquid film diffusion. The MnO₂-MWCNT NHs were effective in removing BPS and NPs across varying water chemistry (pH and ionic strength) and natural water matrices, including river, estuary, and seawater. A 2 g/L dose of MnO₂-MWCNT NHs was sufficient for simultaneous NPs and BPS removal, while excellent reusability over multiple cycles demonstrated the potential for long-term water treatment applications of the material. Overall, MnO₂-MWCNT NHs offer a sustainable, efficient, and cost-effective solution for water remediation, with promising implications for global pollution control efforts.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101038"},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143103953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analgesics in wastewater matrix: A comprehensive review on occurrence, toxicity, and sustainability assessment of biological, tertiary, and hybrid treatment processes","authors":"Shalini Singh ,&nbsp;Abhradeep Majumder ,&nbsp;Pubali Mandal ,&nbsp;Manoj Kumar Yadav","doi":"10.1016/j.enmm.2024.101039","DOIUrl":"10.1016/j.enmm.2024.101039","url":null,"abstract":"<div><div>Over the past few decades, increased consumption of pharmaceuticals has led to the prevalence of the pharmaceuticals and their metabolites in various wastewater matrices. Amongst, analgesics are one of the most consumed classes of medicines. These analgesics have complex molecular structures and physicochemical properties that do not favor degradation by conventional biological processes. Furthermore, they pose significant toxicity towards the non-target species and have the potential to disrupt the aquatic environment. Hence, researchers have focused on advanced or tertiary treatment processes, such as adsorption, photocatalysis, and the Fenton process, to remove these recalcitrant analgesics. Although these processes can remove analgesics with a high removal efficiency of around 85%, they fail to perform well with raw wastewater. Hence, hybrid processes have emerged as a wholesome treatment solution for pharmaceutical-contaminated wastewater. In this context, this review paper covers the performance assessment and sustainability of different biological, advanced, and hybrid processes in treating analgesic-contaminated wastewater. It was observed that the biological process alone could only remove around 60–70%, while the average analgesic removal from synthetic water using adsorption, Fenton, and photocatalysis was more than 80%. However, hybrid processes like a combination of constructed wetlands and photocatalysis exhibited more than 80% removal from real wastewater and were more financially and environmentally sustainable. This review provides a comprehensive idea of how analgesics, in particular, are ubiquitous in the aqueous environment and suggests how they can be removed sustainably by providing a comprehensive overview of all existing treatment systems.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101039"},"PeriodicalIF":0.0,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143105000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of Congo red adsorption using oxidated nitrogen-doped carbon nanotubes","authors":"Alicia E. Chávez-Guajardo ,&nbsp;Luis Octavio Solis-Sanchez ,&nbsp;María Medina-Llamas ,&nbsp;Brenda I. Orea-Calderón ,&nbsp;Florentino López-Urías ,&nbsp;Emilio Muñoz-Sandoval ,&nbsp;Verónica L. Medina-Llamas","doi":"10.1016/j.enmm.2024.101037","DOIUrl":"10.1016/j.enmm.2024.101037","url":null,"abstract":"<div><div>This work reports the synthesis of nitrogen-doped multilayer carbon nanotubes (N-MWCNTs). The N-MWCNTs were subjected to mild oxidation in air at different temperatures and exposure times to obtain a variety of composites from N-MWCNTs with iron oxide nanoparticles up to mainly nanostructured hematite in its alpha phase (α-Fe₂O₃). X-ray diffraction allowed us to track the transformation path of the N-MWCNTs have a cross oxidation time. Each composite was fully characterized. FTIR analysis revealed that the oxidated N-MWCNTs exhibited a high content of carboxylic and carbonyl functional groups. Raman spectroscopy characterization shows a decrease in the D-band intensity and an increase in the 2D-band intensity as the oxidation temperature and oxidation time increase. For instance, the 5 min oxidized N-MWCNTs at 620 °C show a 3 % decrease in both the I_D/I_G and I_2D/I_G ratios. At 10 min at 620 °C, a 10 % decrease in the I_D/I_G ratio and a 15 % increase in the I_2D/I_G ratio were observed. The former results indicate the opening of the CNTs tips and the exposure of the graphitic layers as oxidation time increases. The TEM micrographs can easily corroborate the former trends. The performance of the pristine and oxidized N-MWCNTs was evaluated for the adsorption of Congo red (CR) as a model pollutant. The results indicate that mild oxidation temperatures (620 °C) and short oxidation times favor CR adsorption with a faster adsorption equilibrium than pristine N-MWCNTs. The percentage removal of pristine N-MWCNTS was 33 %. The oxidized samples at 620 °C had a higher adsorption removal of CR up to 36 % and 43 % when oxidation time was 5 and 10 min. The results demonstrate that oxidation thermal treatment reduces amorphous carbon and promotes the opening of the CNTs, increasing the active sites on the surface of the material, which facilitates interaction with CR.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101037"},"PeriodicalIF":0.0,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143104521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One step facile green synthesis of ZnFe2O4-ZnO Nanocomposite: Efficient photocatalytic activity towards organic dyes under visible light and photoluminescence applications","authors":"E.Vinay Kumar ,&nbsp;R. Harini ,&nbsp;Anitha ,&nbsp;B.E. Kumara Swamy ,&nbsp;G. Nagaraju","doi":"10.1016/j.enmm.2024.101036","DOIUrl":"10.1016/j.enmm.2024.101036","url":null,"abstract":"<div><div>One of the major risks to the ecosystem is the pollution of water resulting from organic dyes. For scientists, the elimination of dyes from water has remained a challenge. The development of heterostructure photocatalysts featuring enhanced photogenerated charge carriers has attracted significant interest in recent times. The development of a trustworthy, reliable, affordable, and environmentally friendly process for the fabrication of photocatalysts is the main motivation for this research project. In this research work, we presented the easy, affordable green solution combustion process for synthesizing ZnFe₂O₄-ZnO nanocomposite (NCs) using <em>Btea monosperma</em> leaves extract. The synthesized heterostructure is extensively characterized using XRD, FT-IR, UV–Vis, SEM EDX, and PL Spectroscopy. Studies on photoluminescence emission were conducted, and the CIE diagram revealed green emission. The characteristic green emission of ZFO NCs facilitates the tracing of LFPs on a variety of surfaces. Hence, ZFO NCs may therefore have use in the field of forensic sciences. Under visible light, the photocatalyst exhibits a remarkable 95 % degradation efficiency for Rose Bengal dye. Additionally, the ZnFe₂O₄-ZnO heterostructure’s reusability was examined, and even after four cycles, the level of photocatalytic activity did not drop much. Therefore, it is a potential photocatalyst for the processing of organic colours.</div></div>","PeriodicalId":11716,"journal":{"name":"Environmental Nanotechnology, Monitoring and Management","volume":"23 ","pages":"Article 101036"},"PeriodicalIF":0.0,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143104520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}