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1.
Chemosphere ; 355: 141838, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38561159

RESUMO

MXene is recognized as a promising catalyst for versatile applications due to its abundant metal sites, physicochemical properties, and structural formation. This comprehensive review offers an in-depth analysis of the incorporation of carbon into MXene, resulting in the formation of MXene-carbon-based composites (MCCs). Pristine MXene exhibits numerous outstanding characteristics, such as its atomically thin 2D structure, hydrophilic surface nature, metallic electrical conductivity, and substantial specific surface area. The introduction of carbon guides the assembly of MCCs through electrostatic self-assembly, pairing positively charged carbon with negatively charged MXene. These interactions result in increased interlayer spacing, reduced ion/electron transport distances, and enhanced surface hydrophilicity. Subsequent sections delve into the synthesis methods for MCCs, focusing on MXene integrated with various carbon structures, including 0D, 1D, 2D, and 3D carbon. Comprehensive discussions explore the distinctive properties of MCCs and the unique advantages they offer in each application domain, emphasizing the contributions and advancements they bring to specific fields. Furthermore, this comprehensive review addresses the challenges encountered by MCCs across different applications. Through these analyses, the review promotes a deeper understanding of exceptional characteristics and potential applications of MCCs. Insights derived from this review can serve as guidance for future research and development efforts, promoting the widespread utilization of MCCs across a broad spectrum of disciplines and spurring future innovations.


Assuntos
Carbono , Elétrons , Nitritos , Elementos de Transição , Transporte de Elétrons , Condutividade Elétrica
2.
Chemosphere ; 292: 133400, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34974048

RESUMO

Herein, the facile synthesis of copper(II) and benzene-1,3,5-tricarboxylate (Cu-BTC) and copper nanoporous carbon (Cu@NPC) for the electrochemical detection of diphenylamine (DPA) was systematically investigated. The Cu-BTC and Cu@NPC materials structural, morphological, and thermal stability were evaluated and confirmed using FE-SEM, HR-TEM, XRD, FT-IR, and TGA. The electrocatalytic behavior of sensor materials was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It is presumed that the structural stability and synergic effect exhibited in Cu@NPC are favorable for enhanced sensitivity and selectivity towards the detection of DPA. The Cu@NPC exhibited a wide linear range (0.09-396.82 µM) and the lowest limit of detection (5 nM). Furthermore, the real sample analysis of the sensor for the detection of DPA in apples and pears confirms its potential capability in practical application.


Assuntos
Carbono , Nanoporos , Antioxidantes , Cobre , Difenilamina , Técnicas Eletroquímicas , Eletrodos , Frutas , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Polymers (Basel) ; 12(6)2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32517332

RESUMO

Superhydrophilic zwitterions on the membrane surface have been widely exploited to improve antifouling properties. However, the problematic formation of a <20 nm zwitterionic layer on the hydrophilic surface remains a challenge in wastewater treatment. In this work, we focused on the energy consumption and time control of polymerization and improved the strong hydrophilicity of the modified polyvinylidene difluoride (PVDF) membrane. The sulfobetaine methacrylate (SBMA) monomer was treated with UV-light through polymerization on the PVDF membrane at a variable time interval of 30 to 300 s to grow a poly-SBMA (PSBMA) chain and improve the membrane hydrophilicity. We examined the physiochemical properties of as-prepared PVDF and PVDF-PSBMAx using numeric analytical tools. Then, the zwitterionic polymer with controlled performance was grafted onto the SBMA through UV-light treatment to improve its antifouling properties. The PVDF-PSBMA120s modified membrane exhibited a greater flux rate and indicated bovine serum albumin (BSA) rejection performance. PVDF-PSBMA120s and unmodified PVDF membranes were examined for their antifouling performance using up to three cycles dynamic test using BSA as foulant. The PVDF-modified PSBMA polymer improved the antifouling properties in this experiment. Overall, the resulting membrane demonstrated an enhancement in the hydrophilicity and permeability of the membrane and simultaneously augmented its antifouling properties.

4.
Mikrochim Acta ; 186(2): 59, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30617429

RESUMO

A hydrothermal route is reported for the preparation of a composite consisting of sheet-like glucose-derived carbon and nickel oxide nanoparticles. The nanocomposites were prepared at different annealing temperatures and exploited as electrode materials for amperometric (i-t) determination of hydrazine (N2H4) and hydrogen peroxide (H2O2) at trace levels. The performances of the sensors were assessed by cyclic voltammetry and amperometry detection using a rotating disk electrode (RDE) technique. The modified electrode annealed at ca. 300 °C was found to exhibit the best electrocatalytic performance in terms of sensitive and selective detection of N2H4 and H2O2 even in the presence of interfering species. The electrode is inexpensive, robust, easy to prepare in large batches, highly stable, and has a low overpotential. H2O2 can be sensed, best at a working voltage of typically 0.13 V vs Ag/AgCl; rotationg speed 1200 rpm) over a wide concentration range (0.01 to 3.9 µM) with a detection limit of 1.5 nM. N2H4 can be sensed, best at a working voltage of typically 0.0 V within the concentration range from 0.5 µM to 12 mM with an excellent detection limit of 1.5 µM. Thus, this cost-effective and robust modified electrode, which may be readily prepared in large batch quantity, represents a practical platform for industrial sensing. Graphical abstract Schematic of the hydrothermal method for synthesis of carbon and nickel oxide nanoparticle composites (GCD/NiO-150, GCD/NiO-300, and GCD/NiO-450). The composite was used for the electro-oxidation of hydrazine (N2H4) and hydrogen peroxide (H2O2) by cyclic voltammetry and amperometry (i-t).

5.
J Colloid Interface Sci ; 501: 350-356, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28463766

RESUMO

A Facile approach of one-step synthesis was employed to prepare porous CuO at different annealing temperature and characterized by using numerous analytical techniques. Moreover, the electrochemical sensing application of CuO modified glassy carbon electrode was studied and recorded using various electrochemical techniques. From the results, it was interpreted that the CuO prepared at 350°C exhibits satisfactorily electrochemical determination of Acetylsalicylic acid (ASA) with unique sensitivity, linear range and limit of detection of about 831.65µA mM-1cm-2, 0.1-714µM and 0.037µM respectively. The proposed sensor also shows good electrocatalytic performance in real sample analysis with acceptable results.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Aspirina/análise , Cobre/química , Técnicas Eletroquímicas/métodos , Carbono/química , Técnicas de Química Sintética , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Temperatura Alta , Porosidade , Comprimidos
6.
J Colloid Interface Sci ; 490: 719-726, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27951514

RESUMO

Well-defined CoS nanorods (NR) were synthesized using a simple hydrothermal method, and were tested as an electrode material for electro-oxidation of vanillin. The NR material was characterized with regard to morphology, crystallinity, and electro-activity by use of appropriate analytical techniques. The resulting CoS NR@Nafion modified glassy carbon electrode (GCE) exhibited efficient electro-oxidation of vanillin with a considerable linear range of current-vs-concentration (0.5-56µM vanillin) and a detection limit of 0.07µM. Also, food samples containing vanillin were studied to test suitability for commercial applications.


Assuntos
Antioxidantes/análise , Benzaldeídos/análise , Chocolate/análise , Cobalto/química , Técnicas Eletroquímicas/métodos , Nanotubos/química , Eletrodos , Polímeros de Fluorcarboneto/química , Análise de Alimentos , Limite de Detecção , Nanotubos/ultraestrutura , Oxirredução
7.
J Mater Chem B ; 3(30): 6285-6292, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262747

RESUMO

Herein, we report a simple and facile synthesis strategy of MnO2/carbon nanotubes decorated with a nanocomposite of Pt nanoparticles using a simple electrodeposition method. The Pt/MnO2/f-MWCNT modified electrode were characterized by several analytical and spectroscopy techniques and were adopted as a composite for a novel catechin sensor. The as-prepared Pt/MnO2/f-MWCNT modified glassy carbon electrode (GCE) exhibited a smaller peak potential separation (ΔEp), and electron transfer kinetics during the oxidation reaction of catechin. This can be attributed to the larger effective surface area, greater porosity, and more reactive sites on the Pt/MnO2/f-MWCNT-modified GCE. Notably, we achieved a very low detection limit (under optimized conditions) of catechin ca. 0.02 µM (S/N = 3); the linear range is 2-950 µM with excellent sensitivity. The real time application of catechin in red wine, black tea, and green tea samples with excellent performance. The proposed sensor was successfully developed and the advantages of low cost, ease of preparation, long-term stability, and good reproducibility were demonstrated which are superior to recently reported modified electrodes, thereby enabling practical industrial applications.

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