Transition metal chalcogenides (TMCs) have great potential in diverse electrochemical technologies owing to their unique characteristics. In the present work, we portray the design and synthesis of ...Vanadium selenide (V2Se9)/reduced graphene oxide (rGO) forming a two-dimensional (2D) hybrid nanocomposite via a simple hydrothermal method. The successfully synthesized nanocomposite underwent in-depth surface and morphological characterizations by XRD, Raman spectroscopy, XPS, TEM, STEM and its potential as an electro catalyst was investigated by using glassy carbon electrode (GCE) for the detection of 2,4,6-trichlorophenol (TCP). The structural features favored a high charge transfer ratio, high surface area as well as excellent conductivity and catalytic activity. The V2Se9/rGO/GCE modified electrode showed a low charge transfer resistance (Rct) of 54.057 Ω cm2, a decent detection limit (LOD) of 35.07 nM and a very high sensitivity of 22 μA μM−1 cm−2 in a working range of 0.001 μM–1150 μM. This is due to the active proton interaction, surface enhancement, and positive synergistic effect between rGO and V2Se9. The proposed sensor has good detection potential in agricultural soil, river water, fish, and beverage samples like wine and apple juice. The obtained results from our investigation would elucidate the application of the catalyst in electrochemical sensors.
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•Vanadium selenide (V2Se9) is prepared through facile hydrothermal process.•V2Se9 ultrasonically treated with reduced graphene oxide (rGO) forming composite.•V2Se9/rGO is used for the first time in electrochemical sensor application.•2,4,6-Trichlorophenol (TCP) detection capacity using V2Se9/rGO is 35.07 nM.•The sensor showed a high sensitivity of 22 μA μM−1 cm−2 for TCP detection.
The exploration of graphitic carbon nitride (g-C3N4), a two-dimensional (2D) metal-free polymer semiconducting material, is largely discussed due to its large specific surface area, high electrical ...conductivity, thermal stability, and adaptable electronic structure. The adaption of sulfur (S) and phosphorous (P) atoms into the layers of g-C3N4 increases the electrochemical performance of detecting nilutamide (NT). The aggregation severity can be decreased by integrating S/P into g-C3N4, thereby improving surface area and electrical conductance. The g-C3N4, S/gC3N4, P/g-C3N4, and S/P/g-C3N4 were studied with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Ultraviolet visible spectroscopy (UV), Thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET). The well-assigned S/P/g-C3N4 exhibited a good crystalline structure with more active sites for improved electron transfer toward NT detection. Both differential pulse voltammetry (DPV) and amperometry (IT) was studied for NT detection. The electrochemical studies were done with a linear range of 0.019–1.17 μM to 5.36–1891.98 μM in DPV and 0.01 μM–158.3 μM in IT technique. The attained limit of detection in DPV analysis was 3.2 nM and with IT analysis 2.4 nM. The nanocomposite S/P/g-C3N4 shows good selectivity towards NT. The fabricated electrode showed excellent repeatability, reproducibility, and stability, with a significant recovery range in real sample analysis.
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•The two-dimensional metal free polymeric material graphitic carbon nitride (g-C3N4) was employed. in the present study.•To booster the performance of g-C3N4 sulfur (S) and phosphorous (P) were substituted into g-C3N4 carbon structure.•S/P/g-C3N4 with more active sites showed superior electrochemical performance towards nilutamide (NT) detection.•The fabricated electrode revealed good repeatability, reproducibility, stability for NT reduction analysis.•The composite material is more appropriate and enriched with more significant features opting good performances.
•g-C3N4/CeVO4/SPC electrode is used to determine anti-inflammatory mesalazine drug.•The g-C3N4/CeVO4/SPCE has shown a good sensitivity of 18.92 μA μM−1 cm−2.•A wide working range of 0.002−380 μM and ...LOD of 0.00547 μM is exhibited using DPV.•Real-time analysis is carried in biological and pharmaceutical samples.
Rare-earth metal vanadate has gained much interest in recent years due to its excellent catalytic properties and chemical stability in electrochemical sensors. In this study, we have explored the electrochemical activity of graphitic-carbon nitride (g-C3N4) and hierarchical 3D cerium vanadate (CeVO4) by using screen printed carbon paste electrode (SPCE) for detection of mesalazine (MEZ). Successfully, g-C3N4 and CeVO4 were synthesized by using a simple hydrothermal process, and then to form a nanocomposite ultrasonication procedure is approached. To confirm the structural and morphological parameters X-ray diffraction (XRD), X-ray photoelectron spectroscopy, Field-emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM) is being utilized. The g-C3N4/CeVO4/SPCE modified electrode has exhibited superior electrocatalytic performance in detecting MEZ with lower Rct value and with the high active surface area when compared with other electrodes. The prepared sensor has shown good sensitivity 18.92 μA μM−1 cm−2 and with a huge working range of 0.002−380 μM, with a promising trace-level limit of detection of about 0.00547 μM by using differential pulse voltammetry (DPV). Henceforth, g-C3N4/CeVO4/SPCE was carried out to subject real-time application in detecting MEZ in various biological, river water, and pharmaceutical samples which resulted in excellent recovery stating the chosen sensor is applicable in real-time analysis.
•Novel Sn doped Zinc oxide hexagonal micro discs anchored are on rGO.•Lattice constant parameters of Wurtzite hexagonal ZnO structures is analyzed.•Sn-ZnO/rGO/GCE exhibited an ultra-low LOD of 7.3 nM ...to linear range 0.01–170 µM.•The sensitivity of the sensor is 14.10 µA µM−1 cm−2 towards flutamide (FLU).•Real-time monitoring is carried out in river and biological samples.
Prostate cancer is one of the major causes of death around the globe leading to cancer deaths in the US standing at a second position. Flutamide is one of the important drugs which is utilized in clinical diagnosis. Even though over usage and improper discharge leads to very serious harm to both living and environmental bodies. In this aspect developing a sensor for ultra-trace level detection of flutamide is very much indeed with selectivity, stability, and reproducibility. Herein, we report a facile synthesis of hexagonal Sn doped zinc oxide (Sn-ZnO) anchored on reduced graphene oxide (rGO) hybrid nanocomposite in discriminating reduction of flutamide. As per prepared Sn-ZnO/rGO nanocomposite has exhibited good catalytic performance when compared to bare and other modified electrodes. Resulting in inactive sites, large surface areas, synergic effects, and crystalline growths. Noticeable merits include the wide linear range of 0.01 to 170 µM and Limit of detection (LOD) of 7.3 nM with an excellent sensitivity of 14.10 µA µM−1 cm−2 and satisfying stability. The modified electrode was successfully applied as a real-time analysis in both biological and water bodies with promising recoveries.
In this study, the simple sonochemical synthesis of functionalized carbon black (f-CB) anchored with tungsten carbide (WC) is used to prepare a novel electrocatalyst for the electrochemical detection ...of furazolidone (FU) by modifying screen-printed carbon electrodes (SPCE). X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy were utilized to investigate the crystal structure, surface morphology and elemental composition of the hybrid composite. The results confirmed the successful formation of uniformly distributed flake-like WC on the surface of f-CB. Due to its peculiar and outstanding morphological structure, an f-CB/WC/SPCE electrode has an enriched electroactive surface area of 0.4105 cm
2
. The electrocatalytic efficiency of furazolidone was studied using cyclic voltammetry and amperometric techniques. The f-CB/WC composite displayed an outstanding synergic effect in detecting the ultra-level presence of FU, with a limit of detection of around 0.6 nM and an ultra-dynamic range of 0.001-1150 μM, which outshone other reported FU sensors. Therefore, it is evident that the preparation method can be successfully applied to bovine albumin serum and pharmaceutical tablets with acceptable recovery.
In this study, the simple sonochemical synthesis of functionalized carbon black (f-CB) anchored with tungsten carbide (WC) is used to prepare a novel electrocatalyst for the electrochemical detection of furazolidone (FU) by modifying screen-printed carbon electrodes (SPCE).
Abstract
The current study reports a facile simple, low-cost electrochemical sensor in the detection of nitrofurantoin (NFT) by using NiFe/
f
-MWCNT hybrid composite as a promising electrocatalyst. ...NFT is an antibiotic drug that is extensively using in pharmaceuticals and also in animal food production which causes a severe threat for both human and animal environments. Extending the residues of NFT are left into rivers, soils, lakes, and groundwaters either found or discharged leading health issues. To this NiFe/
f
-MWCNT composite was synthesized using a hydrothermal mechanism and then ultrasonicated to form a hybrid composite for catalytic evaluation and electrochemical detection of NFT for the very first time. Furthermore, the physicochemical properties of NiFe nanospheres conjugated on
f
-MWCNT are scrutinized using various analytical and spectroscopical techniques. Resulting transmission electron microscopy (TEM) displays a chain like NiFe nanospheres anchored on
f
-MWCNT with a well-defined spherical shape, without any comprehensive agglomeration. The NiFe
/f
-MWCNT screen printed carbon paste electrode (SPCE) displayed an excellent electrocatalytic activity for NFT with a LOD of 0.03 µM and a sensitivity of 11.45 µA µM
−1
cm
−2
. establishing a new selectivity and with the existence of co-interfering compounds. To enhance the practical abilities analysis were performed in Human serum and urine samples which resulted in satisfactory recoveries with high precision and linear accuracy illustrated in Scheme 1.
Monitoring of toxic organic pollutants in the atmosphere is mandatory. Among them, nitrophenols are considered extensive toxic organic pollutants which cause many adverse effects through their ...consumption in the biosphere. A highly precise and sensitive electrochemical sensor to detect 4-nitrophenol based on halloysite nanotubes (HNTs) with silver nanoparticles (AgNPs) decorated on reduced graphene oxide (rGO) is reported. The electrochemical performance of the prepared sensor was estimated through cyclic voltammetry and differential pulse voltammetry. The prepared nanomaterial was employed for the efficient detection of 4-nitrophenol. The fabricated sensor exhibited an extensive working range from 0.1 to 363.9 μM under optimized conditions with a lower detection limit of 48.6 nM for 4-nitrophenol (4-NP). The nanocomposite rGO-HNT-AgNP modified electrode showed a high sensitivity of 35.25 μA μM
−1
cm
−2
, which is much higher than that of the bare electrodes. Furthermore, the evaluation of the developed sensor was done on the basis of practical applicability by determining the presence of 4-NP in real samples obtained from water resources with RSD ± 3.17%.
We report a highly precise and sensitive electrochemical sensor to detect 4-nitrophenol based on halloysite nanotubes with silver nanoparticles decorated on reduced graphene oxide.
The effect of annealing temperature variance on magnesium ferrites (MgFe
2
O
4
) later anchored on reduced graphene oxide (rGO) forming hybrid nanocomposite is demonstrated and its electrochemical ...performance investigated by using a screen-printed carbon paste electrode (SPCE) for detection of the environmental hazardous phenolic compound 4-cyanophenol (4-CY). The MgFe
2
O
4
(MFO–600 °C) displayed an enhanced charge transfer ratio with high conductivity and electrocatalytic activity. To confirm the structural and morphological parameters of the rGO-MFO-2 hybrid micro/nanocomposite, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron microscopy (XPS), and field-emission electron microscopy (FE-EM) with EDX mapping have been utilized. The rGO/MFO-2/SPCE electrode displayed high catalytic performance in detecting 4-CY with good sensitivity of 6.836 μA μM
−1
cm
−2
in a working range 0.001 to 700 μM with a limit of detection of 0.0012 μM by using differential pulse voltammetry (DPV). This is achieved for the active interaction between rGO and MFO-2 active surface site areas resulting in good electrochemical activity and high electron transfer rate. Moreover, 4-CY detection has been performed in the presence of various interferents and through real-time analysis in samples like tap water, industrial river water, and fish which resulted in admirable recovery.
Graphical abstract
Spinel structured aluminates TAl2O4 (T = Mg, Zn, and Cu) were synthesized by a facile hydrothermal method. The resultant enhancement in the electrochemical behavior was achieved due to the covalent ...synergism among the elements coexisting together. Structural and morphological characterizations were performed by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and field emission scanning electron microscopy. MgAl2O4, ZnAl2O4 and CuAl2O4 has displayed same space group Fd3m of Laue class lattice type of the cubic structure as they were synthesized at same temperature (600 °C). CuAl2O4 spinel structure displayed a nanoneedle like structure along with the small sized cylindrical particles alongside to which CuAl2O4 spinel is combined with activated carbon (CuAl/C) and was applied to develop a facile sensor for the electrochemical detection of Acetaminophen (ACAP) using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), which exhibited maximum conductivity, and a substantial electroactive surface area. Finally, the defect-rich composite, CuAl/C, showed excellent sensor performance towards DPV with 21.5 nM limit of detection (LOD) in a wide linear working range of 0.199 μM–165.88 μM ACAP concentration, with a high sensitivity of 19.1221 μA μM−1cm2. Additionally, the sensor showed excellent recovery results in real-time analysis for environmental aquatic samples like industrial wastewater and Tuna Fish.
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•Highly efficient spinel metal aluminates (TAl2O4; T = Mg, Zn, Cu) were synthesized.•The composite shows good catalytic activity by effective covalent synergism.•The composite was utilized to develop a sensor for the detection of anti-analgesic drug ACAP.•Sensitive detection of ACAP was possible with lower LOD at 21.5 nM.•The real-time applicability was successfully implied in environmental aquatic samples.
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•Alkaline earth metal vanadates (S = Mg, Ca, Sr, & Ba) are prepared using hydrothermal approach.•Theoretical calculations prove the origin of MgVO3 phase by satisfying experimental ...results.•MgV/rGO composite shows the selectivity and stability in the electrochemical detection of SF.•Trace level detection of SF is demonstrated through DPV (9 nM) and i-t (3 nM) analysis.•The MgV/rGO electrode demonstrates superior capability of SF detection in real samples.
In this study, well-defined alkaline earth metal vanadates, including MgV, CaV, SrV, and BaV, are synthesized using a simple hydrothermal method, and the crystalline structure, morphology, and structural parameters of the synthesized alkaline earth metal vanadates are investigated and compared. Among the alkaline earth metal vanadates, the MgV shows the unique 3D architecture and MgVO3 hexagonal phase with space group R-3c (167) and a single crystalline phase in V4+ valence state and Mg2+ state revealing cation dimerization in 3d1 honeycomb system. Further Raman spectroscopy with Lorentzian peak fitting and X-ray photoelectron spectroscopy exhibit the phase development with a bucky-ball structure. In order to apply the unique feature, the MgV based composite with reduced graphene oxide as a co-catalyst is prepared to examine the practical application for electrochemical sensing of sulfadiazine. The differential pulse voltammetry and the amperometry i-t analysis demonstrate the superior performance of MgV/reduced graphene oxide composite for the sulfadiazine detection including a superior low limit of detection of 9 nM from the differential pulse voltammetry measurements and 3 nM from the amperometry i-t analysis as well as excellent selectivity and long-term stability. These results are attributed to the enhanced electron transfer and ion diffusion from the synergistic effect of unique MgV and reduced graphene oxide. Moreover, the MgV/reduced graphene oxide composite delivers excellent capability in the detection of sulfadiazine in real samples of human blood serum, industrial wastewater, and pharmaceutical tablet.
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