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1.
Artigo em Inglês | MEDLINE | ID: mdl-39312113

RESUMO

In this study, ω-3-Cu and ω-3-CuO nanocatalysts were investigated for industrial environmental issues. Nowadays, green methodology is very important for addressing industrial environmental issues. In this regard, the current study focuses on ω-3-Cu and ω-3-CuO used for aerobic oxidation and dye decolourization via an eco-friendly approach. The synthesised ω-3-Cu and ω-3-CuO nanocatalysts were characterised using FT-IR, UV, XRD, TEM, GC-MS, 1H and 13C NMR. The results showed that the prepared ω-3-Cu catalyst was almost spherical with forms and sizes typically less than 20 nm and the ω-3-CuO nanocatalyst 10 nm. The ω-3 Cu and ω-3-CuO nanocatalysts were investigated for the conversion of pentan-2-ol into pentan-2-one, which was observed by GC-MS analysis. The ω-3-CuO nanocatalyst decolourised the Brilliant Blue dye more quickly (100% in 30 min) than ω-3-Cu (85% in 60 min) and ω-3 (no colour in 60 min), and Rhodamine B was not decolourised because our ω-3-Cu and ω-3-CuO nanocatalysts inactivated the rhodamine B dye. The aerobic oxidation process using the ω-3-CuO nanocatalyst as the end product of pentan-2-one resulted in a retention time of 30.33. To the best of our knowledge, ω-3-Cu and ω-3-CuO nanocatalysts have not been documented for their application in decolourisation and aerobic oxidation. By highlighting the potential use for the continued advancement and innovation of ω-3-CuO nanocatalysts in the long-term future, cost-effective and eco-friendly methods for producing reusable ω-3-CuO nanocatalysts have the potential to be applied in advanced technical fields, particularly in the areas of dye decolourisation and aerobic oxidation. Finally, we successfully accomplished these processes using the ω-3-CuO nanocatalyst. The ω-3-CuO nanocatalyst evaporated more quickly than the ω-3-Cu and ω-3-CuO nanocatalyst, without any additional energy. ω-3-CuO is the most effective nanocatalyst for dye decolourization and aerobic oxidation (Dual application). ω-3-CuO is used in textile and pharmaceutical industries.

2.
Molecules ; 29(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39274961

RESUMO

Transition metal oxides are considered to be highly promising anode materials for high-energy lithium-ion batteries. While carbon matrices have demonstrated effectiveness in enhancing the electrical conductivity and accommodating the volume expansion of transition metal oxide-based anode materials in lithium-ion batteries (LIBs), achieving an optimized utilization ratio remains a challenging obstacle. In this investigation, we have devised a straightforward synthesis approach to fabricate CuO nano powder integrated with carbon matrix. We found that with the use of a sodium carboxymethyl cellulose (CMC) based binder and fluoroethylene carbonate additives, this anode exhibits enhanced performance compared to acrylonitrile multi-copolymer binder (LA133) based electrodes. CuO@CMC electrodes reveal a notable capacity ~1100 mA h g-1 at 100 mA g-1 following 170 cycles, and exhibit prolonged cycling stability, with a capacity of 450 mA h g-1 at current density 300 mA g-1 over 500 cycles. Furthermore, they demonstrated outstanding rate performance and reduced charge transfer resistance. This study offers a viable approach for fabricating electrode materials for next-generation, high energy storage devices.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39320601

RESUMO

Treating dye-containing wastewater poses numerous challenges due to its high chemical complexity and its persistent nature. Thus, the present study aims to synthesize biochar derived from banana peel (BC) and its nanocomposites with copper oxide nanoparticles (CuOx/BC1-x) for the purpose of adsorptive removing Congo red (CR) dye from water. Several analytical methods were utilized to describe the physicochemical features of the CuOx/BC1-x nanocomposites. It was found that the crystallinity of the nanocomposites gradually improved, while the specific surface area and the surface electronegativity were reduced with increasing x value. The effects of x values (0-0.5), interaction time (10-120 min), adsorbent dose (0.01-0.05 g), initial CR concentration (20-200 mg/L), and the solution temperature (20-60 °C) were evaluated on CR removal. The obtained results revealed that the CuO0.5/BC0.5 nanocomposite showed the highest adsorption efficiency with a maximum adsorption capacity of 233.6 mgg-1. Analysis of the equilibrium experimental data revealed that the Langmuir and the pseudo-2nd-order models were the most proper to describe the current adsorption process. Moreover, the thermodynamics studies demonstrated that the adsorption process was spontaneous, endothermic, and random.

4.
Chemphyschem ; : e202400738, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258742

RESUMO

The electrochemical nitrate reduction reaction (NO3-RR) is a novel green method for ammonia synthesis. The development of outstanding NO3-RR performance is based on reasonable catalyst. Metal oxides have garnered significant attention due to their exceptional electrical conductivity and catalytic properties. Doping serves as an effective strategy for enhancing catalyst performance due to its ability to change the electron cloud distribution and energy levels. In this study, we develop a heterojunction catalyst Fe doped copper oxide nanosheet and cobalt tetroxide nanowire growing on carbon cloth simultaneously (Fe-CuO@Co3O4/CC) via hydrothermal method. The well-designed Fe-CuO@Co3O4/CC has excellent NH3 yield (470.9 µmol h-1 cm-2) and Faraday efficiency (FE: 84.4%) at -1.2 V versus reversible hydrogen electrode (vs. RHE). The heterostructure increases the specific surface area of the catalyst, and the possibility of contact between the catalyst and NO3- ions, enhances the catalytic efficiency. In addition, the catalyst has excellent stability and can stably carry out the electrocatalytic nitrate reduction reaction (NO3-RR), which provides a way for further research on the high-efficiency reduction of nitrate.

5.
Sci Rep ; 14(1): 21246, 2024 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261712

RESUMO

Antibacterial resistance requires an advanced strategy to increase the efficacy of current therapeutics in addition to the synthesis of new generations of antibiotics. In this study, copper oxide nanoparticles (CuO-NPs) were green synthesized using Moringa oleifera root extract. CuO-NPs fabricated into a form of aspartic acid-ciprofloxacin-polyethylene glycol coated copper oxide-nanotherapeutics (CIP-PEG-CuO) to improve the antibacterial activity of NPs and the efficacy of the drug with controlled cytotoxicity. These NPs were charachterized by Fourier transform infrared spectroscopy (FTIR), x-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Antibacterial screening and bacterial chemotaxis investigations demonstrated that CIP-PEG-CuO NPs show enhanced antibacterial potential against Gram-positive and Gram-negative clinically isolated pathogenic bacterial strains as compared to CuO-NPs. In ex-vivo cytotoxicity CIP-PEG-CuO-nano-formulates revealed 88% viability of Baby Hamster Kidney 21 cell lines and 90% RBCs remained intact with nano-formulations during hemolysis assay. An in-vivo studies on animal models show that Staphylococcus aureus were eradicated by this newly developed formulate from the infected skin and showed wound-healing properties. By using specially designed nanoparticles that are engineered to precisely transport antimicrobial agents, these efficient nano-drug delivery systems can target localized infections, ensure targeted delivery, enhance efficacy through increased drug penetration through physical barriers, and reduce systemic side effects for more effective treatment.


Assuntos
Antibacterianos , Ciprofloxacina , Cobre , Polietilenoglicóis , Staphylococcus aureus , Cobre/química , Cobre/farmacologia , Polietilenoglicóis/química , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Animais , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Química Verde , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Linhagem Celular , Infecções Estafilocócicas/tratamento farmacológico , Moringa oleifera/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Nanopartículas/química , Cricetinae
6.
Ecotoxicol Environ Saf ; 284: 116986, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39241609

RESUMO

A new and highly sensitive voltammetric technique was described in this study for the concurrent detection of endocrine disruptors bisphenol A (BPA) and bisphenol AF (BPAF) based on carbon nanocages (CNCs) and copper oxide nanochains (CuONCs). The CNCs was prepared by the solvothermal method and characterized using various techniques. Utilizing the nanocomposite of CNCs and CuONCs, the voltammetric sensor demonstrated outstanding performance in detecting BPA and BPAF simultaneously with distinct oxidation peaks and increased current peaks. The voltammetric signals have linear relationships with the two bisphenols ranging from 0.500 µM to 100 µM with a detection limit of 0.16 µM for BPA and 0.14 µM for BPAF. The newly designed sensor showed reliable consistency, long-term durability and anti-interference ability, and performed well in analyzing real water samples, indicating great potential for environmental monitoring.

7.
Food Chem ; 463(Pt 1): 141101, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39244996

RESUMO

A novel approach for a reliable extraction and analytical characterization of copper oxide nanoparticles (CuONPs) at trace levels on seafood samples was tuned up using single particle inductively coupled plasma mass spectrometry (sp-ICP-MS). Variables for enzymatic extraction of CuONPs were optimised via response surface methodology (RSM) analysis, to maximize both the extracted CuONPs mass and number concentrations without altering their native size and morphology. Analytical performance features of the whole (enzymatic ultrasound-assisted/sp-ICP-MS) approach were thoroughly evaluated. Furthermore, the proposed extraction approach demonstrated higher efficiency compared to an alternative alkaline hydrolysis-based methodology. Finally, nine seafood samples from diverse nature were analysed for CuONPs content and particle size by sp-ICP-MS, revealing significant NPs concentrations in most cases. Attained results enabled the assessment of health risks associated with CuONPs bioaccumulation in seafood organisms.

8.
Sci Rep ; 14(1): 20323, 2024 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223184

RESUMO

Metal oxide nanoparticles(NPs) contain unique properties which have made them attractive agents in cancer treatment. The CuO nanoparticles were green synthesized using walnut shell powder in different calcination temperatures (400°, 500°, 700°, and 900 °C). The CuO nanoparticles are characterized by FTIR, XRD, BET, SEM and DLS analyses. SEM and DLS analyses showed that by increasing the required calcination temperature for synthesizing the NPs, their size was increased. DPPH analysis displayed no significant anti-oxidative properties of the CuO NPs. The MTT analysis showed that all synthesized CuO NPs exhibited cytotoxic effects on MCF-7, HCT-116, and HEK-293 cell lines. Among the CuO NPs, the CuO-900 NPs showed the least cytotoxic effect on the HEK-293 cell line (IC50 = 330.8 µg/ml). Hoechst staining and real-time analysis suggested that the CuO-900 NPs induced apoptosis by elevation of p53 and Bax genes expression levels. Also, the CuO-900 NPs increased the Nrf-2 gene expression level in MCF-7 cells, despite the HCT-116 cells. As can be concluded from the results, the CuO-900 NPs exerted promising cytotoxic effects on breast and colon cancer cells.


Assuntos
Antineoplásicos , Apoptose , Neoplasias da Mama , Neoplasias Colorretais , Cobre , Química Verde , Juglans , Nanopartículas Metálicas , Humanos , Cobre/química , Cobre/farmacologia , Juglans/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Nanopartículas Metálicas/química , Células MCF-7 , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Células HCT116 , Feminino , Células HEK293 , Tamanho da Partícula , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Sobrevivência Celular/efeitos dos fármacos
9.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273116

RESUMO

The removal of pollutants, including heavy metals, from the aquatic environment is an urgent problem worldwide. Actively developing nanotechnology areas is becoming increasingly important for solving problems in the field of the remediation of aquatic ecosystems. In particular, methods for removing pollutants using nanoparticles (NPs) are proposed, which raises the question of the effect of a combination of NPs and heavy metals on living organisms. In this work, we investigated the role of CuO-NPs in changing the toxicity of Cd and Pb salts, as well as the bioaccumulation of these elements in a culture of the microalga Desmodesmus communis. It was found that CuO-NPs at concentrations of 10, 100, and 1000 µg L-1 had no effect on the viability of microalgae cells. On the 14th day of the experiment, Cd at a concentration of 1 mg L-1 reduced the viability index by 30% and, when combined with CuO-NPs, by 25%, i.e., CuO-NPs slightly reduced the toxic effect of Cd. At the same time, in this experiment, when CuO-NPs and Cd were used together, the level of oxidative stress increased, including on the first day in mixtures with 1 mg L-1 Cd. Under the influence of Pb, the cell viability index decreased by 70% by the end of the experiment, regardless of the metal concentration. The presence of CuO-NPs slightly reduced the toxicity of Pb in terms of viability and reactive oxygen species (ROS). At the same time, unlike Cd, Pb without NPs caused ROS production on the first day, whereas the addition of CuO-NPs completely detoxified Pb at the beginning and had a dose-dependent effect on mixtures at the end of the experiment. Also, the introduction of CuO-NPs slightly reduced the negative effect of Pb on pigment synthesis. As a molecular mechanism of the observed effects, we prioritized the provocation of oxidative stress by nanoparticles and related gene expression and biochemical reactions of algae cells. Analysis of the effect of CuO-NPs on the Cd and Pb content in microalgae cells showed increased accumulation of heavy metals. Thus, when algae were cultured in an environment with Cd and CuO-NPs, the Cd content per cell increased 4.2 times compared to the variant where cells were cultured only with Cd. In the case of Pb, the increase in its content per one cell increased 6.2 times when microalgae were cultured in an environment containing CuO-NPs. Thus, we found that CuO-NPs reduce the toxic effects of Cd and Pb, as well as significantly enhance the bioaccumulation of these toxic elements in the cells of D. communis microalgae. The results obtained can form the basis of technology for the nanobioremediation of aquatic ecosystems from heavy metals using microalgae.


Assuntos
Cádmio , Cobre , Chumbo , Nanopartículas Metálicas , Microalgas , Estresse Oxidativo , Chumbo/toxicidade , Chumbo/metabolismo , Cobre/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Microalgas/metabolismo , Microalgas/efeitos dos fármacos , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Bioacumulação , Poluentes Químicos da Água/toxicidade , Espécies Reativas de Oxigênio/metabolismo
10.
J Environ Manage ; 370: 122434, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39265492

RESUMO

Photothermal catalytic oxidation is a promising and sustainable method for the degradation of indoor formaldehyde (HCHO). However, the excessively high surface temperature of existing photothermal catalysts during catalysis hinders the effective adsorption and degradation of formaldehyde under static conditions. Catalyst loading and oxygen vacancies (OVs) modulation are commonly employed strategies to reduce the photothermal catalytic temperature and enhance the efficiency of photothermal catalytic oxidation. In this work, a p-n type CuO/TiO2 heterojunction is successfully loaded onto diatomite using a wet precipitation method. Under the irradiation of a 300W xenon lamp, the prepared composite material achieved a 100% removal rate of HCHO within 2 h, with a 98% conversion rate to CO2, surpassing the performance of both individual photocatalysts and thermocatalysts. Additionally, by adjusting conditions such as light irradiation and temperature, we have demonstrated that this material exhibits synergistic photothermal catalytic properties. Based on HRTEM, XPS, Raman, and EPR analyses, the introduction of diatomite as a catalyst support was shown to effectively increase the number of OVs. Experimental results, along with O2-TPD, photoelectrochemical characterization, and radical detection, demonstrate that the presence of OVs enhances the oxidative efficiency of both photocatalysis and thermocatalysis, as well as the UV-Vis-IR photothermal catalytic performance. The ternary composite material generates weak hydroxyl (•OH) and superoxide (•O2-) radical under high-temperature with dark conditions, indicating its catalytic oxidation activity under this condition. The increase in temperature and the expansion of the spectral range both enhance the generation of these radicals. In summary, this work demonstrates that the use of diatomite as a support increases the material's specific surface area and OVs content, thereby enhancing adsorption and photothermal catalysis. It elucidates the enhanced catalytic degradation mechanism of this mineral-based photothermal catalyst.

11.
Angew Chem Int Ed Engl ; : e202413832, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221719

RESUMO

The multi-carbon (C2+) alcohols produced by electrochemical CO2 reduction, such as ethanol and n-propanol, are considered as indispensable liquid energy carriers. In most C-C coupling cases, however, the concomitant gaseous C2H4 product results in the low selectivity of C2+ alcohols. Here, we report rational construction of mesostructured CuO electrocatalysts, specifically mesoporous CuO (m-CuO) and cylindrical CuO (c-CuO), enables selective distribution of C2+ products. The m-CuO and c-CuO showed similar selectivity towards total C2+ products (≥76%), but the corresponding predominant products were C2+ alcohols (55%) and C2H4 (52%), respectively. The ordered mesostructure not only induced the surface hydrophobicity, but selectively tailored the adsorption configuration of *CO intermediate: m-CuO preferred bridged adsorption, whereas c-CuO favored top adsorption as revealed by in situ spectroscopies. Computational calculations unraveled that bridged *CO adsorbate is prone to deep protonation into *OCH3 intermediate, thus accelerating the coupling of *CO and *OCH3 intermediates to generate C2+ alcohols; by contrast, top *CO adsorbate is apt to undergo the favorable conventional C-C coupling process to produce C2H4. This work illustrates selective C2+ products distribution via mesostructure manipulation, and paves new path into the design of efficient electrocatalysts with tunable adsorption configuration of key intermediates for targeted products.

12.
J Fluoresc ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222210

RESUMO

Understanding the development and performance of UV photodetectors is crucial, given their extensive applications in both military and civilian sectors. The evolution of self-powered photodetectors, especially those based on heterojunction nanostructures, has demonstrated significant potential for enhancing both device efficiency and functionality. By exploring the effects of material composition and structural design, can optimize these devices for improved photoelectric response and energy efficiency. In this study, we prepared the CuO/ZnO NRs heterojunction photodetector on an ITO substrate to enhance photoelectric response of UV detectors. The fabrication process utilized the hydrothermal method and the spin coating technique. The effect of CuO concentration on the optical response of the photodetector under UV radiation at wavelengths of 405 nm and 385 nm was investigated. The samples were characterized using FESSEM, XRD, EDX, and UV-Vis spectra. The device is further distinguished by its standard I-V curves and photocurrent-time curves, which demonstrate the device's behavior under various light conditions. The prepared thin films are polycrystalline, with CuO layers displaying monoclinic phases and ZnO layers exhibiting a hexagonal wurtzite phase. All samples have the potential to exhibit photovoltaic properties and self-powered capabilities. Furthermore, the I-V curve confirms that the photocurrent mechanism of these junctions adheres to the recombination standard, in addition to demonstrating correction behavior. A sample with a CuO concentration of 0.1 M shows the highest photosensitivity, reaching 340,700%, and a photocurrent gain (Iph/Idark) of 3,408 when exposed to light irradiation at 405 nm. Additionally, it exhibits a rapid response time of 0.8 s.

13.
Environ Geochem Health ; 46(10): 371, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167279

RESUMO

Copper-based nanoparticles (NPs) are gradually being introduced as sustainable agricultural nanopesticides. However, the effects of NPs on plants requires carefully evaluation to ensure their safe utilization. In this study, leaves of 2-week-old lettuce (Lactuca sativa L.) were exposed to copper oxide nanoparticles (CuO-NPs, 0 [CK], 100 [T1], and 1000 [T2] mg/L) for 15 days. A significant Cu accumulation (up to 1966 mg/kg) was detected in lettuce leaves. The metabolomics revealed a total of 474 metabolites in lettuce leaves, and clear differences were observed in the metabolite profiles of control and CuO-NPs treated leaves. Generally, phenolic acids and alkaloids, which are important antioxidants, were significantly increased (1.26-4.53 folds) under foliar exposure to NPs; meanwhile, all the significantly affected flavonoids were down-regulated after CuO-NP exposure, indicating these flavonoids were consumed under oxidative stress. Succinic and citric acids, which are key components of the tricarboxylic acid cycle, were especially increased under T2, suggesting the energy and carbohydrate metabolisms were enhanced under high-concentration CuO-NP treatment. There was also both up- and down-regulation of fatty acids, suggesting cell membrane fluidity and function responded to CuO-NPs. Galactinol, which is related to galactose metabolism, and xanthosine, which is crucial in purine and caffeine metabolism, were down-regulated under T2, indicating decreased stress resistance and disturbed nucleotide metabolism under the high CuO-NP dose. Moreover, the differentially accumulated metabolites were significantly associated with plant growth and its antioxidant ability. Future work should focus on controlling the overuse or excessive release of NPs into agricultural ecosystems to limit their adverse effects.


Assuntos
Antioxidantes , Carbono , Cobre , Lactuca , Folhas de Planta , Lactuca/metabolismo , Lactuca/efeitos dos fármacos , Antioxidantes/metabolismo , Cobre/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Carbono/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Metabolômica
14.
Mikrochim Acta ; 191(9): 555, 2024 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172272

RESUMO

A novel signal amplification strategy was developed by combining near-infrared light with MoS2/CuO/Au nanocomposite for building a colorimetric immunoassay. First, MoS2/CuO/Au nanocomposite was synthesized by precipitation and photoreduction methods and characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). MoS2/CuO/Au nanocomposite has oxidase-like activity and can oxidize TMB to form a blue product (TMBox). Further, the catalytic oxidation of TMB was accelerated under near-infrared (NIR) laser radiation. The sandwich-type colorimetric immunoassay was constructed using MoS2/CuO/Au nanocomposite. Under the enhancement of near-infrared light, carcinoembryonic antigen (CEA) was sensitively detected in the range 0.1 to 40 ng/mL with the limit of detection of 0.03 ng/mL. Moreover, the immunosensor has excellent selectivity and anti-interference, good repeatability, and stability.


Assuntos
Biomarcadores Tumorais , Antígeno Carcinoembrionário , Colorimetria , Cobre , Dissulfetos , Ouro , Raios Infravermelhos , Limite de Detecção , Molibdênio , Nanocompostos , Molibdênio/química , Nanocompostos/química , Cobre/química , Dissulfetos/química , Colorimetria/métodos , Ouro/química , Humanos , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/análise , Imunoensaio/métodos , Técnicas Biossensoriais/métodos , Anticorpos Imobilizados/imunologia
15.
Environ Sci Pollut Res Int ; 31(39): 52511-52522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39147899

RESUMO

Here, the hierarchical mesoporous-activated carbon particles obtained by KOH activation from pistachio shell wastes are modified by both the sulfonation process and CuO doping by hydrothermal heating (CuO@S-doped PSAC) for use as a supercapacitor. It is predicted that the electrochemical performance of the porous carbon electrode material obtained by such CuO doping and sulfonation process will be significantly increased with increased Faradaic capacitance. The electrochemical performance of CuO@S doped PSAC composite is systematically investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge/discharge (GCD) in the presence of 1 M H2SO4, 1 M Na2SO4, and 1 M NaOH as electrolytes. The CuO@S doped PSAC-based electrode shows excellent stability with high specific capacitance up to 397.16 F/g at 0.1 A/g and 92.64% retention. Furthermore, FTIR, SEM, XRD, EDS, and nitrogen adsorption/desorption analyses are used for the characterisation of the obtained composites. Based on a significant supercapacitor performance, the synthesis strategy of carbon-based electrode material containing sulfonation and CuO modifications derived from agricultural biomass waste material is predicted to be a valuable example.


Assuntos
Biomassa , Carbono , Cobre , Capacitância Elétrica , Eletrodos , Carbono/química , Cobre/química , Porosidade
16.
J Hazard Mater ; 478: 135437, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39121735

RESUMO

Pendimethalin (PM) is an organic pollutant (herbicide), and systematic studies on PM degradation are scarce. The efficient degradation of PM in water remains a challenge that requires to be addressed. Herein, for the first time, elemental Co was doped into HKUST-1 using a solvothermal method to generate Co3O4/CuO@C via pyrolysis. The as-prepared catalyst was used to activate peroxymonosulfate (PMS) for PM degradation, obtaining a PM degradation efficiency of 98.2 % after 30 min. The assessment of the effects of various factors on the degradation efficiency revealed that 1O2 dominated PM degradation, whereas the contribution of SO4•- was negligible. Although 3Co3O4/CuO@C exhibited a good degradation performance against other organic pollutants, its degradation performance in real water was poor. The carbon layer reduced metal-ion leaching (Co and Cu), and the synergistic interactions between Co3O4 and CuO promoted PMS activation. The roles of the components of 3Co3O4/CuO@C in PM degradation by activated PMS were investigated in the presence of CoIV and Co-OOSO3-. Two possible PM degradation pathways were systematically proposed, and the toxicity of the intermediates was analyzed. Finally, a mechanism for PM degradation by 3Co3O4/CuO@C-activated PMS was proposed.

17.
Sensors (Basel) ; 24(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39204984

RESUMO

The effectiveness of copper oxide-modified electrochemical sensors using different polymers is being studied. The commercial powder was sonicated in an isopropyl alcohol solution and distilled water with 5 wt% polymers (chitosan, Nafion, PVP, HPC, α-terpineol). It was observed that the chitosan and Nafion caused degradation of CuO, but Nafion formed a stable mixture when diluted. The modified electrodes were drop-casted and analyzed using cyclic voltammetry in 0.1 M KCl + 3 mM [Fe(CN)6]3-/4- solution to determine the electrochemically active surface area (EASA). The results showed that α-terpineol formed agglomerates, while HPC created uneven distributions, resulting in poor stability. On the other hand, Nafion and PVP formed homogeneous layers, with PVP showing the highest EASA of 0.317 cm2. In phosphate-buffered saline (PBS), HPC and PVP demonstrated stable signals. Nafion remained the most stable in various electrolytes, making it suitable for sensing applications. Testing in 0.1 M NaOH revealed HPC instability, partial dissolution of PVP, and Cu ion reduction. The type of polymer used significantly impacts the performance of CuO sensors. Nafion and PVP show the most promise due to their stability and effective dispersion of CuO. Further optimization of polymer-CuO combinations is necessary for enhanced sensor functionality.

18.
Food Sci Nutr ; 12(8): 5907-5921, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39139956

RESUMO

The emergence of drug-resistant strains in tuberculosis treatment underscores the urgency for novel therapeutic approaches. This study investigates the anti-tuberculosis activity of green-synthesized copper oxide (CuO) nanoparticles (NPs) using garlic and astragalus extracts. The physicochemical characterization of the nanoparticles confirms successful synthesis, followed by assessment of their antibacterial properties and safety profile. Rats infected with Mycobacterium tuberculosis are treated with nanocomposites derived from garlic extract at doses of 50 mg/kg and 100 mg/kg body weight. Evaluation includes the analysis of Early secreted antigenic target of 6 kDa (ESAT-6) expression and confirmation of antibodies through molecular assays. Administration of garlic and nanocomposites demonstrates significant inhibitory effects on tuberculosis progression in rats, validated by safety assessments and antibacterial efficacy. Notably, the 100 mg/kg dosage exhibits pronounced mitigation of tuberculosis-induced oxidative stress and lung damage. In conclusion, the combined administration of garlic extracts and green-synthesized nanocomposites shows promising efficacy in reducing tuberculosis infection, highlighting a potential avenue for anti-tuberculosis interventions.

19.
Sci Rep ; 14(1): 18961, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39147855

RESUMO

This work has applied metal-organic frameworks (MOFs) with high adsorbability and catalytic activity to develop electrochemical sensors to determine free chlorine (free-Cl) concentrations in aqueous media. A zeolitic imidazolate frameworks, Zn(Hmim)2 (ZIF-8) has been synthesized and incorporated with CuO nanosheets to decorate a glassy carbon electrode (GCE) and provide a new sensor for free-Cl determination. The as-prepared ZIF-8 and CuO-ZIF-8 composites have been characterized by FESEM, EDX, XRD, and FT-IR analyses. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) utilized to characterize the CuO-ZIF-8/GC modified electrode electrochemically, demonstrated the ability of the sensor to measure free-Cl concentration. Using differential pulse voltammetry (DPV) and under the optimal conditions, the prepared CuO-ZIF-8/GC modified electrode showed a linear response in the 0.25-60 ppm range with a 12 ppb detection limit (LOD) for free-Cl concentration. Finally, the fabricated sensor was applied to analyze free-Cl from actual swimming pool water samples with promising 97.5 to 103.0% recoveries.

20.
Anal Chim Acta ; 1319: 342969, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39122279

RESUMO

BACKGROUND: Ethanol gas sensors are widely used in driving safety, security, and clinical respiratory monitoring applications. However, most ethanol sensors are large and exhibit poor stability owing to their integrated controller and high-temperature operation. Moreover, the development of wireless controller-free room-temperature ethanol sensors with long-term reliability is challenging. RESULTS: In this study, a wireless room-temperature ethanol gas antenna sensor was developed by combining a Cu radiation electrode with vertical graphene (VG) embedded with CuO@Cu nanoparticles and a polydimethylsiloxane (PDMS) dielectric substrate filled with cysteine (Cys). In the patch-antenna sensor, changes in the ethanol gas concentration resulted in frequency shift differences in the generation and transmission processes of the synchronized sensing signal. The VG-Cu/Cys-PDMS ethanol gas sensor had a detection range of 50-2100 ppm and a low limit of detection (LOD) of 0.112 ppm, with a response/recovery time of only 20/21 s for 1200 ppm ethanol, thus demonstrating superior long-term stability and satisfactory humidity tolerance. Therefore, the synergistic sensitization mechanism between the VG sensing/radiation layer and Cys-PDMS substrate was investigated. SIGNIFICANCE: This approach effectively addresses the issues of low-temperature operation, miniaturization, and long-term reliability. The proposed patch-antenna gas sensor is suitable for large-scale production owing to its use of industrial chemical vapor deposition technology and could be used to develop Internet-of-Things gas sensor nodes owing to its wireless propagation of electromagnetic waves with sensing information.

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