Functionalized Carbon Nanofiber Research Articles

Mg-MOF-Derived hierarchical porous carbon fiber electrodes for efficient capacitive deionization

The development of metal organic framework (MOF) functionalized carbon nanofiber with high flexibility has attracted significant attention in the fields of electrochemistry and capacitive deionization. Especially, MOF materials with alkaline earth metal centers offer advantages such as cost-effectiveness, non-toxicity, and ease of preparation. In this study, we introduced a simple strategy for synthesizing hierarchical porous carbon nanofibers derived from Mg-MOF-containing electrospun fiber (HCNF/Mg) and explored their application in capacitive deionization (CDI). The resulting HCNF/Mg exhibits a flexible structure and boasted specific surface area (908.42 m2/g), thus providing an efficient electrosorption interface to facilitate the fast ionic diffusion. Under optimum conditions, the CDI desalination capacity achieves 22.10 mg/g, accompanied with an ultrafast adsorption rate of 2.2 mg/g/min. Furthermore, this material demonstrates remarkable stability, maintaining the capacity of 90 % over 40 cycles, positioning it as a promising candidate for practical CDI applications.

Cerium vanadate/functionalized carbon nanofiber composite for the electrochemical detection of nitrite

This study presents a facial and quick electrochemical sensor platform that offers remarkable water and food safety applications. The present work represents a study of the synthesis and characterization for efficient cerium vanadate (CeVO4) with a functionalized carbon nanofiber (f-CNF) decorated electrode, which is a highly effective electrode modifier for sensitive nitrite detection. The CeVO4 nanoparticles were synthesized using the facial hydrothermal technique, and a composite (CeVO4@f-CNF) was prepared using the sonication method. Afterward, the produced materials were confirmed with spectroscopic and microscopic analysis. The electrochemical behavior of nitrite was studied through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The DPV analysis depicts an excellent linear range of 0.1˗1033 μM and a promising detection limit of 0.004 μM for the proposed electrode. The CeVO4@f-CNF electrode was applied to detect nitrite in water and meat samples. The proposed electrochemical sensor attributes the significant results towards the detection of nitrite.

Hydrothermally Synthesized Cerium Phosphate with Functionalized Carbon Nanofiber Nanocomposite for Enhanced Electrochemical Detection of Hypoxanthine

This work presents the detection of hypoxanthine (HXA), a purine derivative that is similar to nucleic acids who overconsumption can cause health issues, by using hydrothermally synthesized cerium phosphate (CePO4) followed by a sonochemical approach for CePO4 decorated with a functionalized carbon nanofiber (CePO4@f-CNF) nanocomposite. The formation of the nanocomposite was confirmed with X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). A CePO4@f-CNF nanocomposite is used to modify a glassy carbon electrode (GCE) to analyze the electrochemical detection of HXA. Cyclic voltammetry (CV), Electrochemical impedance spectroscopy (EIS), and Differential pulse voltammetry (DPV) were used to examine the electrochemical properties of the composite. As a result, the modified electrode exhibits a larger active surface area (A = 1.39 cm2), a low limit of detection (LOD) at 0.23 µM, a wide linear range (2.05–629 µM), and significant sensitivity. Therefore, the CePO4@f-CNF nanocomposite was used to study the real-time detection in chicken and fish samples, and it depicted significant results.

A Ce2MgMoO6 double perovskite decorated on a functionalized carbon nanofiber nanocomposite for quantification of ciprofloxacin in milk and honey samples: Density functional theory interpretation

In this study, a novel Ce2MgMoO6/CNFs (cerium magnesium molybdite double perovskite decorated on carbon nanofibers) nanocomposite was developed for selective and ultra-sensitive detection of ciprofloxacin (CFX). Physical characterization and analytical techniques were used to explore the morphology, structure, and electrocatalytic characteristics of the Ce2MgMoO6/CNFs nanocomposite. The sensor has a wide linear range (0.005–7.71 μM and 9.75–77.71 μM), a low limit of detection (0.012 μM), high sensitivity (0.807 μA μM−1 cm−2 nM), remarkable repeatability, and an appreciable storage stability. Here, we used density functional theory to investigate CFX and oxidized CFX as well as the locations of the energy levels and electron transfer sites. Furthermore, the Ce2MgMoO6/CNFs-modified electrode was successfully tested in food samples (milk and honey), indicating an acceptable response with a recovery percentage and relative standard deviation of less than 4%, which is comparable to that of GC-MS. Finally, the developed sensor exhibited high selectivity and stability for CFX detection.

Synergistic activation of lamellar bismuth selenide anchored functionalized carbon nanofiber for detecting hazardous carbendazim in environmental water samples

Pesticides pollute natural water reservoirs through persistent accumulation. Therefore, their toxicity and degradability are serious issues. Carbendazim (CBZ) is a pesticide used against fungal infections in agricultural crops, and its overexploitation detrimentally affects aquatic ecosystems and organisms. It is necessary to design a logical, efficient, and field-deployable method for monitoring the amount of CBZ in environmental samples. Herein, a nano-engineered bismuth selenide (Bi2Se3)/functionalized carbon nanofiber (f-CNF) nanocomposite was utilized as an electrocatalyst to fabricate an electrochemical sensing platform for CBZ. Bi2Se3/f-CNF exhibited a substantial electroactive surface area, high electrocatalytic activity, and high conductivity owing to the synergistic interaction of Bi2Se3 with f-CNF. The structural chemical compositions and morphology of the Bi2Se3/f-CNF nanocomposite were confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FESEM). Electrochemical analysis was carried out using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). The voltammetry and impedance experiments exposed that the Bi2Se3/f–CNF–modified GCE has attained adequate electrocatalytic function with amended features of electron transportation (Rct = 35.93 Ω) and improved reaction sites (0.082 cm2) accessible by CBZ moiety along with exemplary electrochemical stability (98.92%). The Bi2Se3/f-CNF nanocomposite exhibited higher sensitivity of 0.2974 μA μM−1cm−2 and a remarkably low limit of detection (LOD) of 1.04 nM at a broad linera range 0.001–100 μM. The practicability of the nanocomposite was tested in environmental (tap and pond water) samples, which supports excellent signal amplification with satisfactory recoveries. Hence, the Bi2Se3/f-CNF nanocomposite is a promising electrode modifier for detecting CBZ.

The synergy of gadolinium vanadate/acid functionalized carbon nanofiber for effective determination of anti-psychotic drug chlorpromazine hydrochloride in human serum sample

Psychotropic medications were widely prescribed to deal with neuroleptics but prolonged usage or overdosage of these medicines may end up in brain shrinkage along with irreversible antipsychotic disorders. Therefore, it is crucial to quantitatively detect such medications to prevent potential harm. An effective electrochemical technique was used to detect chlorpromazine hydrochloride (CPZ-HCl). This study details the synthesis of GdVO4/f-CNF through a reliable hydrothermal procedure. The focus was on understanding the structural and crystallographic characteristics, as well as gaining insights into the morphology of the electrode modifier, to comprehend their impact on the overall electrochemical system. The GdVO4/f-CNF nanocomposite's element combination generates non-linear cumulative effects makes the nanocomposite an effective transducer with an enhanced surface. The enhancement is achieved through integrated redox cycling, primarily characterized by anodic response, resulting in analyte regeneration and an amplified output signal. The electrocatalytic behavior was optimized by the cyclic voltammetry (CV) technique, and validated by the sensitive differential pulse voltammetry (DPV) approach, used to assess the accuracy. From the validation study, sensitivity and limit of detection (LOD) have been calculated as 6.18 µA µM−1 cm−2 and 38.5 nM. Finally, the fabricated sensor was successfully tested in human serum samples for practicability application. Overall, this research provides a valuable contribution to the field by offering an advanced and reliable method for the electrochemical detection of psychotropic medications, addressing a critical need for the safety and well-being of individuals undergoing such treatments.

Enhanced electrochemical detection of tartrazine in beverages and liquid soap via nickel phosphide-adorned functionalized carbon nanofibers

BackgroundTartrazine (TAT) is a widely used food colorant dye, offering an orange-yellow hue in various products such as foods, cosmetics, and pharmaceuticals. Despite its popularity, TAT is banned in several countries due to its potential health risks, including respiratory issues, migraines, and skin allergies. Moreover, TAT is linked with adverse effects on human physiology, including mutagenicity, biliary cirrhosis, changes in liver and kidney functions, and neurodegeneration at varying doses. Consequently, the detection of this food additive is crucial for safeguarding human health and protecting aquatic organisms. MethodsIn this study, a novel sensor was developed for the detection of TAT, utilizing a composite material made from nickel phosphide decorated with functionalized carbon nanofiber (Ni2P@f-CNF). The Ni2P@f-CNF was synthesized and characterized through several techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, field emission-scanning electron microscopy, and elemental mapping. The composite was then integrated with a glassy carbon electrode to create a sensor. The sensor's performance was evaluated in terms of detection limit, linear range, selectivity, sensitivity, reproducibility, repeatability, and long-term stability. Main FindingsThe developed Ni2P@f-CNF composite sensor displayed a lower detection limit of 0.011 µM and a broad linear range from 0.01 to 1875 µM. Its selectivity and sensitivity were exceptional, primarily due to the catalytic activity of the Ni2P@f-CNF composite towards TAT. The sensor also demonstrated excellent reproducibility, repeatability, and notable long-term stability. Importantly, when applied in real-world scenarios, the sensor successfully detected TAT in soft drink and liquid soap samples, yielding high recovery rates between 97.45 % to 99.37 % and 98.26 % to 99.01 %, respectively, underscoring its potential applicability in practical settings.

Highly dispersed amorphous nano-selenium functionalized carbon nanofiber aerogels for high-efficient uptake and immobilization of Hg(II) ions

Owing to the strong Hg−Se interaction, Se-containing materials are promising for the uptake and immobilization of Hg(II) ions; compared with metal selenides or selenized compounds, elemental Se contains the highest ratio of Se. However, it remains a challenge to fully expose all the potential Se binding sites and achieve high utilization efficiency of elemental Se. Through rational design on the structure, dispersity, and size of materials, Se/CNF aerogels composed of abundant well-dispersed and amorphous nano-Se have been prepared and applied for the high-efficient uptake and immobilization of Hg(II) ions. The well-dispersion of nano-Se increases the exposure of Se sites, the amorphous structure benefits the easy cleavage of Se−Se bonds, the 3D porous networks of aerogels permit fast ions transport and easy operation. Benefiting from the combination effect of strong Hg−Se interaction and sufficient exposure of Se-enriched sites, the Se/CNF aerogels demonstrate strong binding ability (Kd = 3.8 ×105 mL·g-1), high capacity (943.4 mg·g-1), and preeminent selectivity (αMHg > 100) towards highly toxic Hg(II) ions. Notably, the utilization efficiency of Se in Se/CNF aerogels is as high as 99.5%. Moreover, the strong Hg−Se interaction and extraordinary stability of HgSe could minimize the environmental impact of the spent Se/CNF adsorbents after its disposal.

An Ag/C Core–Shell Composite Functionalized Carbon Nanofiber Film as Freestanding Bifunctional Host for Advanced Lithium–Sulfur Batteries

An Ag/C Core–Shell Composite Functionalized Carbon Nanofiber Film as Freestanding Bifunctional Host for Advanced Lithium–Sulfur Batteries

Signal Amplification for Detection of Nilutamide in Three-Dimensional Electrochemical Sensor Using Copper Metal–Organic Framework Decorated Carbon Nanofibers

The extensive use of antibiotics has rapidly spread antibiotic resistance, which poses significant health risks to humans. Unfortunately, despite this pressing issue, there is still a lack of a reliable on-site detection method for the residues of antibiotics, such as nilutamide (Nlu). Consequently, there is an urgent need to develop and perfect such a detection method to effectively monitor and control antibiotic residues. In this study, the hydrothermal development of copper-metal-organic framework (Cu-MOF) polyhedrons on the functionalized carbon nanofiber (f-CNF) matrix allowed for the detection of Nlu in biological liquids via a sensitive amperometry technique. Further electrochemical detection of Nlu took place with the cyclic voltammetry (CV) technique Cu-MOF/f-CNF. Analytical and spectroscopic approaches were used to confirm the successful synthesis of Cu-MOF/f-CNF. The prepared material was decorated on the surface of GCE and performed as an electrochemical Nlu sensor, with a broad linear range of 0.01 to 141.4 μM and 2 nM as a lower limit of detection. In addition, the composites had a large surface area and many dedicated sites, which improved electrocatalysis. In practical applications, Cu-MOF/f-CNF/GCE provides a novel strategy for improving electrochemical activity by measuring Nlu concentrations in biological samples.

Neodymium(III) Vanadate-Decorated Functionalized Carbon Nanofiber Nanocomposite: An Electrochemical Tool for Tartrazine Monitoring

Neodymium(III) Vanadate-Decorated Functionalized Carbon Nanofiber Nanocomposite: An Electrochemical Tool for Tartrazine Monitoring

Supercapacitance of an integrated structure of nickel cobalt metal-organic framework decorated on electrospun functionalized carbon nanofiber

In order to enhance the electrochemical efficiency of supercapacitors, novel active electrode materials are being developed. This study provides a unique method to synthesize an integrated structure consisting of a nickel-cobalt metal-organic framework (NiCo-MOF) on functionalized carbon nanofiber (f-CNF) utilizing a single-step solvothermal method. Physicochemical characterization confirmed the successful synthesis of the integrated system of NiCo-MOF@f-CNF. This novel structure has the potential to significantly improve the electrochemical properties of the initially prepared material for use in supercapacitors. The synthesized electrode has a higher specific capacitance/capacity value of 788 F g−1 (315.2 C g−1) at 1 A g−1 and high cycling stability. The developed hybrid device exhibited a promising specific energy of 8.6 Wh kg−1 and a high specific power of 1147 W kg−1, demonstrating potential for practical applications. The current study suggests that the proposed material can be a viable electrode for high-efficiency supercapacitors.

Strontium phosphate/functionalized carbon nanofiber composite: A promising electrode material for amperometric detection of flufenamic acid

Anti-inflammatory drug pollution and its potentially disastrous consequences have recently emerged as a major health issue worldwide because of its widespread use in inadequate environments. Among, Flufenamic acid (FFA) is a class of anti-inflammatory drugs widely used for therapeutic treatments, and its over usage causes severe issues in the biological systems. In this work, a particle–like strontium phosphate (Sr2P2O7) was prepared. The efficiency was increased by making a composite with functionalized carbon nanofiber (F-CNF) and used to detect FFA. The prepared individual materials (Sr2P2O7 and F-CNF) and the composite (Sr2P2O7@F-CNF) were confirmed by various spectroscopy techniques. The electrochemical studies of Sr2P2O7@F-CNF were done by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). A sensitive i-t amperometry technique was used for the determination of FFA. The attained results show that Sr2P2O7@F-CNF shows a higher active surface area (A= 0.197 cm2), a wide linear range of 0.001–80.8 µM, a low detection limit of 0.9 nM, and higher selectivity. Finally, the Sr2P2O7@F-CNF was taken to the real-time analysis with the water and urine samples. The result shows an acceptable recovery range of ± 97.50–99.66 % for the water and urine samples.

Screen printed electrodes on interfacial Pt–CuO/carbon nanofiber functional ink for real-time qualification of cell released hydrogen peroxide

Screen printed electrode (SPE) on carbon-based inks exhibits promising applications in biosensing, environment protection and food safety. We report here a unique carbon-based material comprising Pt–CuO nanocrystal interfacially anchored on functionalized carbon nanofiber (Pt–CuO@FCNF) and its functional ink to build SPE for ultrasensitive detection of cell released H2O2. Pt–CuO@FCNF is fabricated using a one-pot and mass production method through direct pyrolysis of Pt and CuO precursors together with FCNF. FCNF with 1-D structure and high electrical conductivity can interfically anchor Pt–CuO nanocrystal, which synergically promotes rich active site and catalytic activity towards H2O2. Pt–CuO@FCNF exhibits a wide linear response of 0.4 μM–11 mM, a low detection limit of 17 nM, a fast response time of 1.0 s, and good selectivity. Eventually, Pt–CuO@FCNF SPE realizes real-time and ultrasensitive qualification of H2O2 released from both normal and cancer cells.

Alkaline earth metal stannate TSnO3 (T = Ca and Sr) entrapped functionalized carbon nanofiber composites: active electrocatalysts for the determination of hydroxychloroquine in environmental samples

A novel aspect of the present study is that it attempts to reduce the negative environmental impacts caused by conventional toxic solvents.

Lanthanum nickelate spheres embedded acid functionalized carbon nanofiber composite: An efficient electrocatalyst for electrochemical detection of food additive vanillin

Contemporary food marketing is ruined by flavor enhancers rather than emphasizing the nutritional value of food. Vanillin is an overexploited flavor enhancer added to food items, thereby necessitating its detection. In this study, an electrochemical sensor was designed using a modified electrode made up of La2NiO4 functionalized carbon nanofiber (f-CNF) to effectively detect vanillin in food samples. To confirm the successful formation of La2NiO4/f-CNF, structural and morphological studies were performed using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Further electrochemical analysis was performed using cyclic voltammetry and differential pulse voltammetry techniques, which resulted in high sensitivity (0.2899 µA·μM−1·cm−2) and low limit of detection (LOD) (6 nM). This modified electrode material was tested in food samples, which showed an excellent response with recovery percentage and is a promising electrocatalyst for vanillin detection.

Rational design of Nd2O3 decorated functionalized carbon nanofiber composite for selective electrochemical detection of carbendazim fungicides in vegetables, water, and soil samples

Abuse of carbendazim (CBZ) leaves excessive pesticide residues on agricultural products, which endangers human health because of the residues' high concentrations. Hence, a composite consisting of functionalized carbon nanofibers (f-CNF) with neodymium oxide (Nd2O3) was fabricated to monitor CBZ at trace levels. The Nd2O3/f-CNF composite-modified electrode displays higher electro-oxidation ability towards CBZ than Nd2O3 and f-CNF-modified electrodes. The combined unique properties of Nd2O3 and f-CNF result in a substantial specific surface area, superior structural stability, and excellent electrocatalytic activity of the composite yielding enhanced sensitivity to detecting CBZ with a detection limit of 4.3 nM. Also, the fabricated sensor electrode can detect CBZ in the linear concentration range of up to 243.0 μM with high selectivity, appropriate reproducibility, and stability. A demonstration of the sensing capability of CBZ in vegetables, water, and soil samples was reported paving the way for its use in practical applications.

Lithium-enhanced functionalized carbon nanofibers as a mixed electronic/ionic conductor for sulfide all solid-state batteries

Despite the recent advancement of sulfide all-solid-state lithium batteries, the choice of their respective components yet requires further comprehensive investigations into their functionality and compatibility. While the development of cathode materials and sulfide electrolytes appears to be greatly advanced, there seems a lack of attention on carbon conductive additives. As sulfide electrolytes are unstable with conventional carbon conductive additives, it is necessary to develop conductive additives with a satisfactory electronic conductivity and good chemical/electrochemical stability with sulfide electrolytes. This study proposes a new mixed conductor based on carbon nanofiber (CNF), namely lithium-enhanced functionalized carbon nanofiber (LF-CNF), exhibiting a greatly enhanced Li-ion conductivity with a little compensation of their electronic conductivity. By utilizing LF-CNF, a discharge capacity of ca. 198 mAh g−1 at 0.05C and ca. 148mAh g−1 after 50 cycles at 0.1C were achieved from the cathode composite of LiNi0.8Co0.1Mn0.1O2, argyrodite solid electrolyte and LF-CNF (70:30:5 in mass). Furthermore, LF-CNF appears to reduce detrimental cation mixing after storage in Ar-atmosphere over one month and at high voltage cycling of 4.5 V. Our work highlights that the conductivity tuning of conductive additives offers a great performance enhancement for high-energy sulfide electrolyte based solid-state batteries.

Ultrasensitive electrochemical sensor for the detection of carbamazepine based on gadolinium vanadate nanostructure decorated functionalized carbon nanofiber nanocomposite

The gadolinium vanadate nanostructure decorated functionalized carbon nanofiber (GdVO4/f-CNF) nanocomposite was prepared by the hydrothermal method, which is fabricated on a glassy carbon electrode (GCE) for the determination of carbamazepine (CBZ). The structural morphology of the hydrothermally synthesized GdVO4/f-CNF material was investigated by several spectroscopy methods such as FESEM, HRTEM, EDS-mapping, XRD, XPS, and Raman. Moreover, the electrical conductivity of our synthesized material was inspected by the electrochemical impedance spectroscopy (EIS) analysis, and the electrochemical performance towards CBZ was inspected by the cyclic voltammetry (CV) and amperometry (AMP) analysis under optimized conditions. The AMP determination of CBZ exhibits the lowest level LOD of 0.0018 μM and a good linear range of 0.01–157 μM. Additionally, our proposed sensor was used to determine the CBZ in the pharmaceutical and, human urine samples which have exposed the acceptable recoveries.

Coral reef-like zinc niobate nanostructures decorated functionalized carbon nanofiber as electrode modifier for detection of oxidative stress biomarker: 3-nitro-L-tyrosine

Oxidative stress can transform immunologic disorders to malignancy by enhancing the effect of pathogenic factors associated with adverse health problems. Biomarkers generated during oxidative stress are essential in assessing the in vivo condition of the cell for evaluating health and diagnosing the disease at an early stage, prognosis, benign and effectual drug development, and testing the drug efficacy. 3-Nitro-L-tyrosine is an oxidative stress biomarker produced from L-tyrosine through nitration mediated by active metabolites. Thus, precise detection of 3-NO2-Tyr in the biological medium is significantly important to monitor the cell environment. Consequently, a novel electrochemical sensing platform had been designed using ZnNb2O6 nanostructures anchored f-CNF as a glassy carbon electrode modifier. The crystalline and structural features, morphology, and elemental composition of ZnNb2O6/f-CNF nanocomposite were keenly verified. The synchronic activation of ZnNb2O6/f-CNF nanocomposite for effective detection of 3-NO2-Tyr is mainly due to the synergic effect between its counterparts. Accordingly, the fabricated sensor possesses a remarkably low limit of detection (0.021 μM) with a good linear range, and sensitivity is noted to be 7.745 μA/μM⋅cm⁻2. The consistency of this sensor was evinced through real-time monitoring of 3-NO2-Tyr in urine and saliva samples which is beneficial in monitoring the pathological situation.