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1.
Inorg Chem ; 63(6): 3019-3027, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38286799

RESUMO

Developing efficient and robust electrode materials for electrochemical sensors is critical for real-time analysis. In this paper, a hierarchical holmium vanadate/phosphorus-doped graphitic carbon nitride (HoVO4/P-CN) nanocomposite is synthesized and used as an electrode material for electrochemical detection of hydrogen peroxide (H2O2). The HoVO4/P-CN nanocomposite exhibits superior electrocatalytic activity at a peak potential of -0.412 V toward H2O2 reduction in alkaline electrolytes while compared with other reported electrocatalysts. The HoVO4/P-CN electrochemical platform operated under the optimized conditions shows excellent analytical performance for H2O2 detection with a linear concentration range of 0.009-77.4 µM, a high sensitivity of 0.72 µA µM-1 cm-2, and a low detection limit of 3.0 nΜ. Furthermore, the HoVO4/P-CN-modified electrode exhibits high selectivity, remarkable stability, good repeatability, and satisfactory reproducibility in detecting H2O2. Its superior performance can be attributed to a large specific surface area, high conductivity, more active surface sites, unique structure, and synergistic action of HoVO4 and P-CN to benefit enhanced electrochemical activity. The proposed HoVO4/P-CN electrochemical platform is effectively applied to ascertain the quantity of H2O2 in food and biological samples. This work outlines a promising and effectual strategy for the sensitive electrochemical detection of H2O2 in real-world samples.

2.
Mikrochim Acta ; 191(5): 245, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578313

RESUMO

An electrochemical sensor is established using an iron titanate (FeTiO3) modified glassy carbon electrode (GCE) to detect nitrofurazone. Various microscopic and spectroscopic analysis was performed to reveal the properties of the prepared FeTiO3 hexagonal nanoplates. The FeTiO3/GCE presents enhanced electrochemical response to nitrofurazone at the peak reduction potential of - 0.471 V with a larger peak current than the bare GCE due to high electrical conductivity, enhanced specific surface area, and abundant active sites. The superior nitrofurazone detection performance includes the low limit of detection of 0.002 µM and the sensitivity of 0.551 µA µM-1 cm-2 in the linear concentration range of 0.01-162.2 µM. The reproducibility and selectivity studies of the FeTiO3/GCE show excellent results with a relative standard deviation of < 5%. The practicability of FeTiO3/GCE is confirmed by monitoring nitrofurazone in actual samples. This work demonstrates that perovskite-type FeTiO3 has great potential in real-world sample analysis, and provides a new way to develop high-performance electrochemical sensors.

3.
Mikrochim Acta ; 191(6): 347, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802574

RESUMO

The synthesis of three-dimensional silver nanopopcorns (Ag NPCs) onto a flexible polycarbonate membrane (PCM) for the detection of nitrofurazone (NFZ) on the fish surface by surface-enhanced Raman spectroscopy (SERS) is presented. The proposed flexible Ag-NPCs/PCM SERS substrate exhibits significant Raman signal intensity enhancement with the measured enhancement factor of 2.36 × 106. This is primarily attributed to the hotspots created on Ag NPCs, including numerous nanoscale protrusions and internal crevices distributed across the surface of Ag NPCs. The detection of NFZ by this flexible SERS substrate demonstrates a low limit of detection (LOD) of 3.7 × 10-9 M and uniform and reproducible Raman signal intensities with a relative standard deviation below 8.34%. It also exhibits excellent stability, retaining 70% of its efficacy even after 10 days of storage. Notably, the practical detection of NFZ in tap water, honey water, and fish surfaces achieves LOD values of 1.35 × 10-8 M, 5.76 × 10-7 M, and 3.61 × 10-8 M, respectively,  which highlights its effectiveness across different sample types. The developed Ag-NPCs/PCM SERS substrate presents promising potential for sensitive SERS detection of toxic substances in real-world samples.


Assuntos
Limite de Detecção , Nanopartículas Metálicas , Nitrofurazona , Prata , Análise Espectral Raman , Análise Espectral Raman/métodos , Prata/química , Nitrofurazona/análise , Nitrofurazona/química , Nanopartículas Metálicas/química , Animais , Peixes , Mel/análise , Água Potável/análise , Cimento de Policarboxilato/química , Membranas Artificiais , Poluentes Químicos da Água/análise , Propriedades de Superfície , Contaminação de Alimentos/análise
4.
Inorg Chem ; 62(4): 1437-1446, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36652943

RESUMO

An electrocatalyst with a large active site is critical for the development of a high-performance electrochemical sensor. This work demonstrates the fabrication of an iron diselenide (FeSe2)-modified screen-printed carbon electrode (SPCE) for the electrochemical determination of furaltadone (FLD). It has been prepared by the facile method and systematically characterized with various microscopic/spectroscopic approaches. Due to advantageous physiochemical properties, the FeSe2/SPCE showed a low charge-transfer resistance value of 200 Ω in 5.0 mM [Fe(CN)6]3-/4- containing 0.1 M KCl. More importantly, the FeSe2/SPCE exhibited superior catalytic performance compared to the bare SPCE for FLD sensing based on the electrochemical response in terms of a peak potential of -0.44 V (vs Ag/AgCl (sat. KCl)) and cathodic response current of -22.8 µA. Operating at optimal conditions, the FeSe2-modified electrode showed wide linearity from 0.01 to 252.2 µM with a limit of detection of 0.002 µM and sensitivity of 1.15 µA µM-1 cm-2. The analytical performance of the FeSe2-based platform is significantly higher than many previously reported FLD electrochemical sensors. Furthermore, the FeSe2/SPCE also has a promising platform for FLD detection with high sensitivity, good selectivity, excellent stability, and robust reproducibility. Thus, the finding above shows that the FeSe2/SPCE is a highly suitable candidate for the electrochemical determination of glucose levels for real-time applications such as in human urine and river water samples.

5.
Molecules ; 28(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37375172

RESUMO

Sweat, a biofluid secreted naturally from the eccrine glands of the human body, is rich in several electrolytes, metabolites, biomolecules, and even xenobiotics that enter the body through other means. Recent studies indicate a high correlation between the analytes' concentrations in the sweat and the blood, opening up sweat as a medium for disease diagnosis and other general health monitoring applications. However, low concentration of analytes in sweat is a significant limitation, requiring high-performing sensors for this application. Electrochemical sensors, due to their high sensitivity, low cost, and miniaturization, play a crucial role in realizing the potential of sweat as a key sensing medium. MXenes, recently developed anisotropic two-dimensional atomic-layered nanomaterials composed of early transition metal carbides or nitrides, are currently being explored as a material of choice for electrochemical sensors. Their large surface area, tunable electrical properties, excellent mechanical strength, good dispersibility, and biocompatibility make them attractive for bio-electrochemical sensing platforms. This review presents the recent progress made in MXene-based bio-electrochemical sensors such as wearable, implantable, and microfluidic sensors and their applications in disease diagnosis and developing point-of-care sensing platforms. Finally, the paper discusses the challenges and limitations of MXenes as a material of choice in bio-electrochemical sensors and future perspectives on this exciting material for sweat-sensing applications.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Dispositivos Eletrônicos Vestíveis , Humanos , Suor/química , Técnicas Biossensoriais/métodos
6.
Langmuir ; 38(33): 10162-10172, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35939572

RESUMO

Binary metal oxides with carbon nanocomposites have received extensive attention as research hotspots in the electrochemistry field owing to their tunable properties and superior stability. This work illustrates the development of a facile sonochemical strategy for the synthesis of a copper bismuthate/graphene (GR) nanocomposite-modified screen-printed carbon electrode (CBO/GR/SPCE) for the electrochemical detection of catechol (CT). The formation of an as-prepared CBO/GR nanocomposite was comprehensively characterized. The electrochemical behavior of the CBO/GR/SPCE toward CT was investigated by voltammetry and amperometry techniques. The fabricated CBO/GR/SPCE manifests an excellent electrocatalytic performance toward CT with a lower peak potential and a higher current value compared to those of CBO/SPCE, GR/SPCE, and bare SPCE. It is attributed to enhanced electro-catalytic activity, synergetic effects, and good active sites of the CBO/GR nanocomposite. Under the electrochemical condition, the CBO/GR/SPCE displayed a wide linear sensing range, trace-level detection limit, acceptable sensitivity, and excellent selectivity. Furthermore, our proposed CBO/GR electrode was employed successfully for CT detection in water samples.


Assuntos
Grafite , Nanocompostos , Carbono , Catecóis , Cobre/química , Técnicas Eletroquímicas , Eletrodos , Grafite/química , Nanocompostos/química
7.
Mikrochim Acta ; 189(9): 315, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927374

RESUMO

The synthesis of manganese cobaltate (MnCo2O4) with the hybrid three-dimensional architecture has been developed as an electrocatalyst for the electrochemical sensing of paraoxon-ethyl (PEL). The detailed physicochemical and structural characterization of MnCo2O4 is meticulously examined. The MnCo2O4-modified screen-printed carbon electrode (SPCE) exhibits good electrocatalytic activity for the reduction of PEL compared with the bare SPCE due to numerous unique properties. By profiting from these advantages, the proposed MnCo2O4/SPCE shows superior sensing performance toward the determination of PEL, including low cathodic peak potential (- 0.64 V), wide detection range (0.015-435 µM), low limit of detection (0.002 µM), high detection sensitivity (2.30 µA µM-1 cm-2), excellent selectivity, and good reproducibility. Notably, the electrochemical performance of the MnCo2O4-based electrocatalyst is superior to those previously reported in the literatures. The practical application of the MnCo2O4/SPCE is effectively assessed in the analysis of food and water samples with satisfied recoveries of 96.00-99.35%. The superior performance of the proposed MnCo2O4 electrocatalyst holds considerable potential for future development of electrochemical sensing platforms.


Assuntos
Manganês , Paraoxon , Carbono/química , Eletroquímica , Limite de Detecção , Reprodutibilidade dos Testes
8.
Inorg Chem ; 60(23): 17986-17996, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34747616

RESUMO

Rational design and construction of the finest electrocatalytic materials are important for improving the performance of electrochemical sensors. Spinel bioxides based on cobalt manganate (CoMn2O4) are of particular importance for electrochemical sensors due to their excellent catalytic performance. In this study, three-dimensional CoMn2O4 with the petal-free, flowerlike structure is synthesized by facile hydrothermal and calcination methods for the electrochemical sensing of roxarsone (RXS). The effect of calcination temperature on the characteristics of CoMn2O4 was thoroughly studied by in-depth electron microscopic, spectroscopic, and analytical methods. Compared to previous reports, CoMn2O4-modified screen-printed carbon electrodes display superior performance for the RXS detection, including a wide linear range (0.01-0.84 µM; 0.84-1130 µM), a low limit of detection (0.002 µM), and a high sensitivity (33.13 µA µM-1 cm-2). The remarkable electrocatalytic performance can be attributed to its excellent physical properties, such as good conductivity, hybrid architectures, high specific surface area, and rapid electron transportation. More significantly, the proposed electrochemical sensor presents excellent selectivity, good stability, and high reproducibility. Besides, the detection of RXS in river water samples using the CoMn2O4-based electrochemical sensor shows satisfactory recovery values in the range of 98.00-99.80%. This work opens a new strategy to design an electrocatalyst with the hybrid architecture for high-performance electrochemical sensing.

9.
Inorg Chem ; 60(7): 4723-4732, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33733761

RESUMO

The construction of novel electrocatalysts for efficient and economic electrochemical sensors is continuously a significant conceptual barrier for the point-of-care technology. Binary metal oxides with heterostructures have gained plenty of attention due to their promising physicochemical properties. Herein, we develop a rapid and sensitive electrochemical probe for the detection of flufenamic acid (FFA) by using a zinc manganate (ZnMnO)-modified electrode. The formation of ZnMnO was confirmed by various analytical techniques, such as X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and field-emission scanning electron microscopy with energy dispersive X-ray spectroscopy and elemental mapping. The ZnMnO-based electrocatalyst, which was used for the electrochemical detection of FFA, shows better performance than the previously reported electrode materials. The ZnMnO assay shows a linear quantitative range from 0.05 to 116 µM with a limit of detection of 0.003 µM and sensitivity of 0.385 µA µM-1 cm-2. Its good electrochemical performance can be ascribed to the large surface area, rapid charge mass transfer, copious active sites, and high carrier mobility. The electrochemical study displays that the fabricated ZnMnO-based sensor has the potential to be applied in the clinical analysis. This work constructs an advanced functional electrode material with a microscale architecture for the point-of-care technology.

10.
Ecotoxicol Environ Saf ; 207: 111276, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931965

RESUMO

Aquatic contamination from the accumulation of pharmaceuticals has induced severe toxicological impact to the ecological environment, especially from non-steroidal anti-inflammatory drugs (NSAIDs). Real-time monitoring of flutamide, which is a class of NSAIDs, is very significant in environmental protection. In this work, we have synthesized the hexagonal-h boron nitride decorated on bismuth oxide (Bi2O3/h-BN) based nanocomposite for the effective electrochemical detection of flutamide (FTM). The structural and morphological information of the heterostructured Bi2O3/h-BN nanocomposite was analyzed by using a sequence of characterization methods. Voltammetric techniques were used to evaluate the analytical performance of the Bi2O3/h-BN modified screen-printed carbon electrode (SPCE) for the FTM detection. The Bi2O3/h-BN modified SPCE displays a synergetic catalytic effect for the reduction of FTM due to large surface area, numerous active sites, fast charge transfer and abundant defects. The proposed electrochemical sensing platform demonstrates high selectivity, low detection limit (9.0 nM), good linear ranges (0.04-87 µM) and short response time for the detection of FTM. The feasibility of the electrochemical sensor has been proved by the successful application to determine FTM in environmental samples.


Assuntos
Bismuto/química , Compostos de Boro/química , Flutamida/química , Nanocompostos/química , Carbono/química , Catálise , Técnicas Eletroquímicas/métodos , Eletrodos
11.
Ecotoxicol Environ Saf ; 208: 111516, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120260

RESUMO

Rapid-monitoring of drugs has attracted tremendous consideration owing to robust global demand for cost-effective and high effectiveness. Binary metal oxides with various morphology have been reported as electrodes for electrochemical sensor to fulfilling the clinical and enviromental requirements. In this study, strontium tungstate (SrWO4) nanoflakes have been successfully prepared via the facile sonochemical method for the first time. The characteristics of as-prepared SrWO4 are systematically measured by various analytical and spectroscopic methods. The SrWO4 nanoflakes are utilized to modify the electrochemical electrode for the sulfadiazine (SDZ) determination. The SrWO4 modified electrode possesses excellent electrocatalytic activity and high recognition capability for the electrochemical detection of SDZ. Impressively, the as-fabricated SrWO4 modified electrode attainted lowest oxidation peak at +0.93 V (vs Ag/AgCl2) with the limit of detection of 0.009 µM, the sensitivity of 0.123 µA µM-1 cm2 and linear detection range of 0.05-235 µM. The enhanced performance of proposed SrWO4-based sensors could be attributed to the catalytic effect, large surface area, good electrical conductivity and physicochemical nature. Notably, the electrocatalytic performances of the SDZ sensors are good as compared to the previous literature, indicating the significance of the newly designed SrWO4 modified electrode. The real-sample diagnosis by the SDZ detection in environmental sample demonstrates the proposed SrWO4-based sensors with good recovery range.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Sulfadiazina/análise , Compostos de Tungstênio/química , Catálise , Técnicas Eletroquímicas/métodos , Eletrodos , Oxirredução , Óxidos/química , Estrôncio
12.
Ecotoxicol Environ Saf ; 190: 110098, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31901811

RESUMO

Prostate cancer is one of the primary causes of death around the world. As an important drug, flutamide has been used in the clinical diagnosis of prostate cancer. However, the over dosage and improper discharge of flutamide could affect the living organism. Thus, it necessary to develop the sensor for detection of flutamide with highly sensitivity. In this paper, we report the synthesis of lanthanum cobaltite decorated halloysite nanotube (LCO/HNT) nanocomposite prepared by a facile method and evaluated for selective reduction of flutamide. The as-prepared LCO/HNT nanocomposite shows the best catalytic performance towards detection of flutamide, when compared to other bare and modified electrodes. The good electrochemical performance of the LCO/HNT nanocomposite modified electrode is ascribed to abundant active sites, large specific surface area and their synergetic effects. Furthermore, the LCO/HNT modified electrode exhibits low detection limit (0.002 µM), wide working range (0.009-145 µM) and excellent selectivity with remarkable stability. Meaningfully, the developed electrochemical sensor was applied in real environmental samples with an acceptable recovery range.


Assuntos
Poluentes Ambientais/análise , Flutamida/análise , Lantânio/química , Nanocompostos/química , Catálise , Argila , Técnicas Eletroquímicas/métodos , Eletrodos , Grafite/química , Humanos , Limite de Detecção , Minerais , Nanotubos/química
13.
Mikrochim Acta ; 187(3): 189, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103346

RESUMO

An electrochemical sensor is described for the determination of catechol (CT) based on the nanocomposite of lanthanum cobaltite supported on graphene nanosheets (LaCo/GNS). The nanocomposite was systematically examined by various analytical and spectroscopic methods. The LaCo/GNS-modified electrode exhibites good electrochemical activity towards CT determination compared to other modified and unmodified electrodes. The electrochemical signal was acquired at a redox potential of 0.21 (Epa) and 0.17 (Epc) Volt (vs. Ag/AgCl). The proposed electrode exhibits low detection limit (1.0 nM), wide working range (0.009-132 µM), and good sensitivity (5.68 µA µM-1 cm-2). The electrochemical nanoprobe has good selectivity over potentially interfering compounds. The electrochemical sensor was applied to the analysis of environmental samples with acceptable recovery. Graphical abstractSchematic representation of electrochemical determination of catechol in the environmental sample analysis using lanthanum cobaltite supported on graphene nanosheets.


Assuntos
Catecóis/química , Técnicas Eletroquímicas/métodos , Grafite/química , Lantânio/química , Minerais/química , Nanocompostos/química
14.
Mikrochim Acta ; 186(3): 141, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30707311

RESUMO

An electrochemical sensor is described for the determination of nilutamide (NLM) in biological fluids. A flexible mat of nitrogen-doped carbon nanofibers (NCNFs) was prepared by electrospinning. This was followed by carbonization and the growth of one-dimensional vanadium tetrasulfide (VS4) nanorods in the circumference of the NCNFs by a solvothermal route. The material was used to modify a glassy carbon electrode (GCE). Cyclic voltammetry and amperometry revealed an excellent electrocatalytic activity of the VS4/NCNF mat towards NLM at a working potential of - 0.57 V (vs Ag/AgCl). The modified GCE has a wide linear range (0.001-760 µM), a low limit of detection (90 pM), good stability, and fast response. It was used to detect NLM in spiked serum and urine samples. Graphical abstract Schematic presentation of a glassy carbon electrode (GCE) composed of free-standing nitrogen-doped carbon nanofibers decorated with vanadium tetrasulfide (Patronite) nanorods (VS4/NCNF). It was fabricated by electrospinning followed by stabilization and carbonization. The GCE responds to nilutamide (NLM) with excellent selectivity and nanomolar sensitivity.


Assuntos
Carbono/química , Imidazolidinas/sangue , Nanofibras/química , Nitrogênio/química , Neoplasias da Próstata/diagnóstico , Compostos de Vanádio/química , Antineoplásicos/sangue , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Humanos , Limite de Detecção , Masculino , Nanocompostos/química , Nanotubos/química , Tamanho da Partícula , Sulfetos/química , Propriedades de Superfície
15.
Mikrochim Acta ; 186(8): 579, 2019 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31352538

RESUMO

Cerium vanadate resembling the shape of a hedgehog were interconnected with carbon nanofibers to give a heterostructure (referred to as CeV/CNF) that exhibits efficient catalytic activity for the electrochemical detection of the drug nilutamide (NLT). The heterostructure material and its modification were characterized by XRD, Raman spectra, XPS, FESEM, TEM, SAED, and EDX. A glassy carbon electrode was modified with the CeV/CNF nanocomposite. Best operated at -0.52 V (vs. Ag/AgCl), it exhibits a very low detection limit (2.0 nM), wide linear range (0.01-540 µM), high sensitivity (1.36 µA µM-1 cm-2) and rapid response towards NLT. It was applied to the determination of NLT in spiked human urine. Graphical abstractSchematic presentation of cerium vanadate interconnected with carbon nanofiber heterostructure for electrochemical determination of prostate cancer drug nilutamide in biological samples.


Assuntos
Antineoplásicos/análise , Técnicas Eletroquímicas/métodos , Imidazolidinas/análise , Nanofibras/química , Vanadatos/química , Antineoplásicos/uso terapêutico , Antineoplásicos/urina , Carbono/química , Cério/química , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Imidazolidinas/uso terapêutico , Imidazolidinas/urina , Limite de Detecção , Masculino , Neoplasias da Próstata/tratamento farmacológico , Reprodutibilidade dos Testes
16.
Water Sci Technol ; 75(5-6): 1128-1137, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272041

RESUMO

Simply coating 1 wt.% of platinum on titanium dioxide (TiO2) surface resulted in simple preparation of platinized TiO2 (Pt-TiO2). This study demonstrated the photodegradation of atrazine (ATZ) using either Pt-TiO2 or TiO2 as a photocatalyst under 352 nm light irradiation. The Pt-TiO2-catalyzed ATZ degradation reached 76% in 3 hours without adding H2O2 solution or aeration, which was more than 10% higher than the TiO2-catalyzed reaction. The decomposition product of Pt-TiO2-catalyzed ATZ degradation was mainly cyanuric acid. Thus, Pt-TiO2 as an effective photocatalyst has three main advantages in the photodegradation of ATZ under 352 nm irradiation. First, the coated Pt can facilitate the generation of appropriate amounts of OH radicals, so it can prevent the formation of over-oxidized TiO2. Second, aeration was not needed. Third, the excited electrons were mainly uni-directionally transferred to the catalyst surface to avoid recombination of electron-hole pairs.


Assuntos
Atrazina/efeitos da radiação , Fotólise , Platina/química , Titânio/efeitos da radiação , Atrazina/química , Catálise/efeitos da radiação , Peróxido de Hidrogênio/química , Cinética , Microscopia Eletrônica de Transmissão , Oxirredução , Espectrofotometria Ultravioleta , Triazinas/química , Difração de Raios X
17.
Sci Rep ; 14(1): 2284, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280908

RESUMO

Graphitic carbon nitride (g-C3N4), an organic photocatalyst was reported to have beneficial properties to be used in wastewater treatment applications. However, g-C3N4, in its bulk form was found to have poor photocatalytic degradation efficiency due to its inherent limitations such as poor specific surface area and fast electron-hole pair recombination rate. In this study, we have tuned the physiochemical properties of bulk g-C3N4 by direct thermal exfoliation (TE-g-C3N4) and examined their photocatalytic degradation efficiency against abundant textile dyes such as methylene blue (MB), methyl orange (MO), and rhodamine B (RhB). The degradation efficiencies for MB, MO, and RhB dyes are 92 ± 0.18%, 93 ± 0.31%, and 95 ± 0.4% respectively in 60 min of UV light irradiation. The degradation efficiency increased with an increase in the exfoliation temperature. The prepared catalysts were characterized using FTIR, XRD, FE-SEM, EDAX, BET, and UV-DRS. In BET analysis, TE-g-C3N4 samples showed improved surface area (48.20 m2/g) when compared to the bulk g-C3N4 (5.03 m2/g). Further, the TE-g-C3N4 had 2.98 times higher adsorption efficiency than the bulk ones. The free radicals scavenging studies revealed that the superoxide radicals played an important role in the photodegradation for dyes, when compared to the hydroxyl radical (.OH) and the photo-induced holes (h+), Photoluminescence (PL) emission and electrochemical impedance spectroscopy (EIS) spectra of TE-g-C3N4 indicated a lowered electron-hole pairs' recombination rate and an increased photo-induced charge transfer respectively. Further, the TE-g-C3N4 were found to have excellent stability for up to 5 cycles with only a minor decrease in the activity from 92% to 86.2%. These findings proved that TE-g-C3N4 was an excellent photocatalyst for the removal and degradation of textile dyes from wastewater.

18.
Sci Total Environ ; 950: 175301, 2024 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-39111428

RESUMO

Two-dimensional layered semiconductor materials as a distinctive class of materials are comprehensively explored for widespread applications due to narrow bandgap, controllable morphology, and tunable metal cation composition. Herein, we constructed a sensing platform of surface enhanced Raman spectroscopy (SERS) by combination of nickel­cobalt layered double hydroxide (NiCo-LDH) microurchins and plasmonic silver nanoparticles (Ag NPs) for fungicide detection of thiabendazole (TBZ). The NiCo-LDHs/Ag-NPs microcomposites consist of NiCo-LDHs microurchins having a large number of nanoneedles deposited with photoreduced Ag NPs. The SERS platform with NiCo-LDHs/Ag-NPs shows an excellent SERS performance for TBZ detection, including an ultra-low detection limit of 1.49 × 10-11 M, a sublime enhancement factor of 1.71 × 109, high uniformity, good reproducibility, and long-term storage stability. The ultrahigh SERS activity of NiCo-LDH/Ag-NPs can be attributed to strong electromagnetic enhancement in the nanoscale gaps between Ag NPs, massive charge transfer through large-area NiCo-LDH/Ag-NPs interfaces, and the synergistic action of electromagnetic and charge transfer mechanisms. Besides, the unique morphology of NiCo-LDHs/Ag-NPs microcomposite provides a broad surface area for adsorption of TBZ molecules for further Raman signal enhancement. The practicability of the proposed SERS platform is confirmed by detecting TBZ in the real samples of apple juice and river water. The exceptional self-cleaning capability of the NiCo-LDHs/Ag-NPs microcomposite with an retention rate of 81.97 % even after the fifth degradation cycle underscores its impressive sustainable reusability and cost-effectiveness. The findings in this work lay the foundation for the development of high-performance SERS platforms to ensure food safety and environmental protection.

19.
ACS Appl Mater Interfaces ; 16(34): 45049-45062, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39141582

RESUMO

Heavy metals are crucial carcinogenic agents threatening the environment and living habituates. Among them, arsenic (As) is an important metalloid that is categorized as a group I toxic carcinogen. Roxarsone (RX) is an organoarsenic antibiotic compound primarily used as a veterinarian drug and growth promoter for poultry animals. The extensive usage of RX increased the accumulation of As in living beings and the ecosystem. Therefore, we have prepared an electrochemical sensor based on 3D bismuth oxybromide with 2D selenium-doped graphitic carbon nitride (BOB/SCN) electrocatalyst for the rapid detection of RX. The elemental and structural details were thoroughly investigated with several spectroscopic techniques. The electrochemical properties were measured by impedance and voltammetric measurements. The electrocatalytic behavior toward the RX was estimated with different voltammetric methods. Therefore, our BOB/SCN-based electrochemical sensor demonstrated a low detection limit (2.3 nM), low quantification value (7.7 nM), optimal sensitivity (0.675 µA µM-1 cm-2), and good linear ranges (0.01-77 and 77-857 µM). Additionally, this sensor showed good electrochemical performance and was applied to monitor the RX in various real samples with remarkable recoveries. Based on these results, our BOB/SCN sensor is a promising electrochemical platform for determining RX.


Assuntos
Bismuto , Técnicas Eletroquímicas , Grafite , Roxarsona , Selênio , Grafite/química , Técnicas Eletroquímicas/métodos , Catálise , Selênio/química , Bismuto/química , Roxarsona/análise , Roxarsona/química , Animais , Compostos de Nitrogênio/química , Limite de Detecção , Nitrilas/química
20.
Chemosphere ; 356: 141895, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38579947

RESUMO

The over-exploitation of antibiotics in food and farming industries ruined the environmental and human health. Consequently, electrochemical sensors offer significant advantages in monitoring these compounds with high accuracy. Herein, MOF-derived hollow Co3S4@MoS2 (CS@MS) heterostructure has been prepared hydrothermally and applied to fabricate an electrochemical sensor to monitor nitrofuran class antibiotic drug. Various spectroscopic methodologies have been employed to elucidate the structural and morphological information. Our prepared electrocatalyst has better electrocatalytic performance than bare and other modified glassy carbon electrodes (GCE). Our CS@MS/GCE sensor exhibited a highly sensitive detection by offering a low limit of detection, good sensitivity, repeatability, reproducibility, and stability results. In addition, our sensor has shown a good selectivity towards the target analyte among other potential interferons. The practical reliability of the sensor was measured by analyzing various real-time environmental and biological samples and obtaining good recovery values. From the results, our fabricated CS@MS could be an active electrocatalyst material for an efficient electrochemical sensing application.


Assuntos
Cobalto , Técnicas Eletroquímicas , Furazolidona , Estruturas Metalorgânicas , Molibdênio , Técnicas Eletroquímicas/métodos , Furazolidona/análise , Catálise , Cobalto/química , Cobalto/análise , Molibdênio/química , Estruturas Metalorgânicas/química , Eletrodos , Dissulfetos/química , Limite de Detecção , Reprodutibilidade dos Testes , Antibacterianos/análise
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