Modified Carbon Nanofibers Research Articles

Hierarchical 2D/1D MOFs/electrospun ZIF-67 modified carbon nanofibers heterostructure electrode for high-performance asymmetric supercapacitor

In this paper, a 2 dimensional (2D) metal–organic frameworks (MOFs) nanosheets grown on 1D ZIF-67 modified carbon nanofibers (CNFs) was designed and fabricated with a hierarchical heterostructure. The hierarchical 2D/1D MOFs/CCNF offers rich electrochemical active sites and favorable ion/electron diffusion pathways. The synergistic effect of Co, CNFs and MOFs from heterostructures contributes to superb electrochemical activities. Benefiting from the hierarchical heterostructures optimized by the mass ratio of ZIF-67/PAN and CCNF/NiMOF as well as the type of substrates, CCNF-20@MOF showed a specific capacity of 361.50 C g−1 at 0.5 A g−1, whose charge storage mechanism is dominated by diffusion control. Meanwhile, a bamboo-derived carbon material (BBC) was designed in the solid-state asymmetric supercapacitor (CCNF-20@MOF//BBC). The device exhibited an energy density of 38.89 Wh kg−1 at the power density of 800.02 W kg−1 and excellent cycling stability, that exceed many MOFs based devices. Moreover, it could be successfully used for LED light-emitting, demonstrating a good application prospect. This work provides a feasible strategy for the improved performance of MOFs and CNFs based materials in the field of energy storage.

Biomass modified carbon nanofibers use for flexible supercapacitor electrodes with thermal conductive performances

The advancement of flexible electrode with excellent energy storage is essential for supercapacitors. Herein, a porous biomass-doped carbon nanofiber@bimetallic oxide composite (B-CNF@NiO/Co3O4) has been prepared as a binder-free flexible electrode. The heteroatoms form biomass not only offer pseudocapacitance but also a multitude of active sites for the grow of bimetallic oxides. The well-grown B-CNF@NiO/Co3O4 shows a high specific capacitance (629.5 F g−1) and the asymmetric flexible supercapacitor (ASC) has an energy density of 31.5 Wh kg−1 at a power density of 757.4 W kg−1. The properties of bimetallic oxides and 3D networks facilitate transportation of interlayer ion, providing a straightforward approach to fabricate non-adhesive flexible electrode with dual functionalities of energy storage. In addition, the thermal conductive experiment demonstrated a favorable thermal conductivity (TC) of 1.06 W m−1 K−1.

Application of functionalized carbon nanofibers as a modifying additive to motor oil

Due to the widespread of lubricants, improving their tribological characteristics remains an important practical task. Among the promising modifying additives, carbon nanomaterials attract special attention. Such materials are found to improve the antifriction characteristics of lubricants and oils. In the present research, carbon nanofibers were synthesized via catalytic pyrolysis of a mixture of light hydrocarbons (C2-C4) over the NiCu catalyst. In order to form functional groups on the surface of carbon nanofibers, they were treated with diluted acids HCl, HNO3, and H2SO4 as well as with concentrated HNO3. The functionalized samples were comprehensively characterized by a set of physicochemical methods including atomic absorption spectroscopy, scanning and transmission electron microscopies, low-temperature nitrogen adsorption, X-ray photoelectron spectroscopy, temperature-programmed desorption/oxidation, and Raman spectroscopy. As defined, the surface oxygen concentration in the samples varies from 3.5 to 16.3 at.%. It was shown that the addition of modified carbon nanofibers to a motor oil leads to an improvement in its tribological characteristics. In particular, the most effective additive was the sample treated with diluted HNO3. The motor oil with this modifying additive exhibited the heating temperature decreased by 10 °C and the contact spot area on the stationary body decreased by 20 %.

A WS2/CNF Nanocomposite for Electrochemical Sensing Applications

It is well recognized that antimicrobials are central to society, but they have also entered the aquatic environment posing risks to public health and our essential ecosystems. Therefore, the detection of antimicrobial drugs at low concentration levels in aquatic environments is essential. In this study, a new composite comprising tannic acid modified carbon nanofibers (CNFs) and WS2 was formed to give CNF/WS2 and used in the electrochemical detection of ornidazole, an antimicrobial drug. Ornidazole is a well-known nitroimidazole and it has been detected in various water bodies. Using the CNF/WS2 composite, a linear concentration range extending from 10 nM to 260 mM ornidazole, with a sensitivity of 1.37 mA mM–1 cm–2 was obtained. Very good selectivity was achieved, and the sensor performed well in the analysis of ornidazole in river water, with recoveries ranging from 88.3 to 107.3%.

First electrochemical nanosensor for ultrasensitive quantification of MET inhibitor, capmatinib based on carbon nanofiber networks incorporated with hybrid nanofiller nanogold-loaded porous acetylene black

In the current study, the first voltammetric method is constructed for the ultrasensitive quantification of capmatinib (CMT), a targeted therapy drug falls within the category of tyrosine kinase inhibitors (TKIs), using a modified carbon nanofibers paste electrode (CNFs-PE). Nanogold-loaded porous acetylene black (Au@PAB) as a conductive hybrid nanofiller incorporating carbon nanofiber networks (CNFs) was synthesized. The surface morphology of the synthesized Au@PAB and the ternary nanocomposite Au@PAB/CNFs was elucidated using various analytical techniques. The results show Au@PAB hybrid nanofiller incorporated CNFs has a critical property that increases electrocatalytic performance. The impact of scan rate, pH, and supporting electrolyte on the electrocatalytic response of CMT was explored on the Au@PAB/CNFs-PE nanosensor. Under optimum adsorptive stripping square-wave voltammetric (AdS-SWV) conditions, the developed probe displayed good sensitivity, selectivity, and a remarkable wide linear dynamic range of 1.0 × 10-8 – 2.0 × 10-5 M of CMT. The low limits of detection (LOD) and quantification (LOQ) were 4.6 nM and 15.4 nM of CMT, respectively. The features of easy operation and good selectivity make this nanosensor a talented candidate for CMT detection in complex samples, as demonstrated by its application in spiked biological samples with good recoveries.

Tin Modified Carbon Nanofibers as an Effective Catalytic Electrode for Bromine Redox Reactions in Static Zinc‐bromine Batteries

AbstractZinc‐bromine batteries (ZBBs) have emerged as a compelling solution for large‐scale energy storage, yet they confront significant technical challenges impeding widespread commercialization. The electrochemical processes within ZBBs rely on a stoichiometric mechanism, where the bromine reaction at the cathode drives the zinc plating reaction on the anode. However, the sluggish electrochemical kinetics of Br2/Br− redox reactions lead to substantial electrochemical polarization, resulting in interruptions in zinc plating and significant voltage losses in ZBBs. This study introduces a new solution to address these challenges by leveraging carbon nanofiber decorated with tin nanoparticles as an efficient catalyst. The catalyst serves to enhance the Br2/Br– redox reaction, effectively reducing voltage losses in ZBBs. When implemented in static ZBB configurations, the Sn/CNF catalysts demonstrate exceptional long‐term stability, achieving an impressive 3000 cycles with minimal voltage loss. In contrast, ZBBs utilizing SnO2 based catalysts experience a substantially higher voltage loss of 736 mV, along with limited and unstable cycling performance. These findings signify a promising approach for the development of catalytic electrodes, paving the way for high‐performance ZBBs with improved efficiency and cycling durability.

Fabrication of hierarchical Co doped Ni3Se4 on ZIF-67 modified carbon nanofibers for high-performance hybrid supercapacitors

Fabrication of hierarchical Co doped Ni3Se4 on ZIF-67 modified carbon nanofibers for high-performance hybrid supercapacitors

Broadband electromagnetic wave absorption using pure carbon aerogel by synergistically modulating propagation path and carbonization degree

Carbon materials were widely used as electromagnetic (EM) wave absorption due to their advantages of light weight, environmental resistance and high electrical conductivity. However, conventional means were typically available by combining carbon and other materials to achieve effective absorption. Herein, a novel strategy using pure carbon aerogel with oriented structure was reported to enhance the EM wave absorption by synergistically modulating the wave propagation path and carbonization degree. The aerogel contained proposed modified carbon nanofibers (MCNF) derived from bacterial cellulose (BC), and core-shell carbon nanofibers @ reduced oxide graphene (CNF@RGO). The oriented structure was induced by the temperature field, which manifests anisotropic EM constitutive parameters (εx ≠ εz) at different directions of incident wave. The carbonization degree was adjusted by varying the carbonization temperature. At the carbonization temperature of 700 °C, the maximum reflection loss and effective absorption bandwidth reached −53.94 dB and 7.14 GHz, respectively, enabling the aerogel to outperform its previous counterparts. To clarify the EM wave mode-of-action in conjunction, physical models of the aerogel were established in addition to finite element simulation and theoretical analysis. Notably, the aerogel with a density of 3.6 mg/cm3 featured ultra-light weight, superhydrophobicity, superior compressibility, and thermal insulation. Our work offers an efficient strategy for designing broadband and multifunctional EM wave absorption materials (EWAMs), promising great potentials in complex stealth equipment.

CoAl2O4 nanoparticles modified carbon nanofibers as high-efficiency bifunctional electrocatalyst: An efficient electrochemical aqueous asymmetric supercapacitors and non-enzymatic electrochemical sensors

The thriving energy demand of the gradually increasing population and modernized life style requires development in energy storage devices for usage in commercial electronic devices. In this particular work, we have explored electrochemical performances of bimetallic oxide CoAl2O4 and tuned its performance by decorating it on the carbon nanofibers. The CoAl2O4/CNFs are synthesized by deep eutectic solvents based hydrothermal method. The synthesized CoAl2O4 nanoparticle was found electrochemically active and the incorporation of CNFs end up boosting, its electrochemical performances as battery-type electrode. The obtained nanocomposites were characterized by various techniques. The electrochemically active CoAl2O4/CNFs exhibited 2.2-fold higher charge storage capacity than CoAl2O4. The CoAl2O4/CNFs exhibited specific capacity as high as 132 C/g at a constant applied current density of 1 A/g in 1 M KOH. The asymmetric device fabricated with CoAl2O4/CNFs electrodes exhibited excellent energy density of 20 Wh/kg at power density of 3000 W/kg. The CoAl2O4/CNFs electrode long-term stability has been minutely observed; the high Coulombic efficiency of 90% and high rate of capacity retention 95 %. In this work, an enzyme-free electrochemical sensor based on CoAl2O4/CNFs composite was developed for the detection of luteolin (LUT). Further modification of CoAl2O4/CNFs composite can improve the high surface area and catalytic capability of the composites. Under the optimal detection conditions, the prepared sensor has good linearity in the detection of LUT within range 30 nM − 73.5 μM with a limit of detection (LOD) of 0.0124 μM (12.4 nM). The stability and selectivity of the sensor is high, and can be used to detect LUT in various real samples.

Silver Nanoparticles on Vertical Graphene As a Stable Lithium Host for Lithium-Metal Batteries

The direct use of lithium metal in batteries is jeopardized by the challenging issues related to lithium dendrites or nonuniform lithium deposition, especially in liquid electrolyte and under high current density. Engineering a lithium host that can promote uniform lithium stripping/plating process has attracted tremendous interest to address the challenges. In this study, we design a hierarchical 3D structure, in which edge-oriented graphene (EOG) nanosheets modified carbon nanofiber (CNF) film is used as a scaffold, decorated with Ag nanoparticles (Ag@EOG-CNF), as the lithium host and current collector. Ag nanoparticles not only render the EOG-CNF lithiophilic but also serve as the seeding sites for lithium nucleation to regulate lithium deposition process. In comparison with the previously reported carbon nanofibers or graphene-based lithium hosts, EOG and Ag modification can significantly increase the available surfaces for lithium deposition with reduced local current density. As a result, the Li/Ag@EOG-CNF electrode showed very stable lithium plating/stripping in both symmetric (~25 mV of overpotential within 1000 h of cycling time at the current density of 2 mA cm-2 and capacity of 2 mAh) and asymmetric (Coulombic efficiency maintains above 98.5% within 200 h of cycling time at the current density of 1 mA cm-2 and capacity of 2 mAh) cells.

Integration of Desulfurization and Lithium–Sulfur Batteries Enabled by Amino‐Functionalized Porous Carbon Nanofibers

Hydrogen sulfide (H2S) is an industrial exhausted gas that is highly toxic to humans and the environment. Combining desulfurization and fabrication of cathode materials for lithium–sulfur batteries (LSBs) can solve this issue with a double benefit. Herein, the amino‐functionalized lotus root‐like carbon nanofibers (NH2‐PLCNFs) are prepared by the amination of electrospinning carbon nanofibers under dielectric barrier discharge plasma. Selective catalytic oxidation of H2S to elemental sulfur (S) is achieved over the metal‐free NH2‐PLCNFs catalyst, and the obtained composite S@NH2‐PLCNFs is further used as cathode in LSBs. NH2‐PLCNFs enable efficient desulfurization (removal capacity as high as 3.46 g H2S g−1 catalyst) and strongly covalent stabilization of S on modified carbon nanofibers. LSBs equipped with S@NH2‐PLCNFs deliver a high specific capacity of 705.8 mA h g−1 at 1 C after 1000 cycles based on the spatial confinement and the covalent stabilization of electroactive materials on amino‐functionalized porous carbon matrix. It is revealed that S@NH2‐PLCNFs obtained by this kind of chemical vapor deposition leads to a more homogeneous S distribution and superior electrochemical performance to the sample S/NH2‐PLCNF‐M prepared by the traditional molten infusion. This work opens a new avenue for the combination of environment protection and energy storage.

An electrochemical sensor based on electrospun MoS2 @SnO2 modified carbon nanofiber composite materials for simultaneously detection of phenacetin and indomethacin.

SnO2 -CNF was prepared by coaxial blending technology, and MoS2 was grown uniformly on SnO2 -CNF composite by adding a hydrothermal post-treatment step. The uniform distribution of MoS2 on one-dimensional SnO2 -CNF can effectively establish a layered three-dimensional structure. Accordingly, the prepared MoS2 -coated SnO2 -CNF composite material has higher surface area and more active sites to obtain better electrochemical performance. We constructed an electrochemical sensor within the composite material with enhanced performance to realize the simultaneous and highly sensitive detection of phenacetin and indomethacin. The sensor has linear ranges of 0.050-7200 μM and 0.05-500 μM, respectively, and the detection limits were 0.016 μM and 0.013 μM. Furthermore, the sensor has good anti-interference ability and stability, which also achieves good recovery rate in the actual sample detection.

In situ preparation of chromium carbide–modified carbon nanofibers as functional electrocatalyst for polysulfide reduction in lithium/sulfur batteries

In situ preparation of chromium carbide–modified carbon nanofibers as functional electrocatalyst for polysulfide reduction in lithium/sulfur batteries

An electrochemical sensor based on CNF@AuNPs for metronidazole hypersensitivity detection

In this paper, an electrochemical sensing platform based on gold nanoparticle modified carbon nanofiber (CNF@AuNPs) as working electrode is proposed for the high sensitivity and selective determination of metronidazole. Meanwhile, the sensor has a large linear response range from 0.1 to 2000 μM, the limit of detection for metronidazole (MNZ) is as low as 0.024 μM. The sensor is simple to prepare and reproducible, and it shows good results in MNZ analysis of tap water.

Electrospinning technology to prepare in-situ Cr2O3 modified carbon nanofibers as dual-function electrode material for vanadium redox battery

Electrospinning is a special fiber manufacturing process, which has the advantages of simple equipment, low cost, and controllable process conditions. Cr2O3 is grown in situ on carbon nanofibers by electrospinning technology. The effects of different contents of Cr2O3 on the morphology and physicochemical properties of carbon nanofibers are systematically studied. The in-situ Cr2O3 nanoparticles were distributed evenly on the carbon nanofibers, which increase the defect degree of the carbon nanofibers. The carbon fiber electrode modified by Cr2O3 has good electrochemical reversibility and activity for vanadium ion redox reaction. At 150 mA·cm−2, compared with pristine cell, the discharge capacity and energy efficiency of modified battery are increased by 77.2% and 6%, respectively. The energy storage performance of modified battery has been significantly improved. The synergistic effect of carbon nanofibers and second phase catalyst Cr2O3 with high catalytic performance can effectively enhance the performance of VRFB.

Synchronously enhanced thermal properties and fracture toughness of epoxy composites through melamine foam templated dispersion of carbon nanofibers

Fabricating the thermally conductive composites through incorporating fillers into polymer matrix is usually at the sacrifice of the fracture toughness. To resolve such contradiction, this work proposed a feasible but highly efficient method of constructing the thermally conductive path in the epoxy composite at extremely low filler content. The polyvinylpyrrolidone (PVP) modified carbon nanofibers (P-CNFs) were coated on the three-dimensional (3D) framework surface of the melamine foam (MF), then the epoxy resin was impregnated into the MF@P–CNF. The results showed that the assembled structure of MF@P-CNFs could be well reserved in the epoxy composite. Consequently, at extremely low P–CNF content (0.8 wt%), the MF@P–CNF/EP sample shows the largely enhanced thermal conductivity (0.4 W/m·K) and glass transition temperature (167 °C) compared with the pure epoxy sample (0.2 W/m·K and 162 °C). Specifically, the composite sample also shows the apparently enhanced fracture toughness. Therefore, it is believed that coating CNFs on the 3D interconnected framework of MF is a promising way to prepare the epoxy composites with good comprehensive properties.

Novel Fe-based metal–organic framework (MOF) modified carbon nanofiber as a highly selective and sensitive electrochemical sensor for tetracycline detection

In this work, a novel electrochemical aptasensor based on Fe-based MOFs was fabricated. To enhance sensitivity to the detection of antibiotics, NH2-MIL-101(Fe)/CNF@AuNPs was synthesized by a combination of hydrothermal, electrospinning, pyrolysis and electrodeposition methods. Subsequently aptamer could be attached to the NH2-MIL-101(Fe)/CNF@AuNPs through “Au-S” bonds. The electrical signals generated from the interaction between antibiotics and aptamers were amplified by the NH2-MIL-101(Fe)/CNF@AuNPs aptasensor, resulting in a significant current/impedance response. Thus, signal generation and amplification were successfully realized. In addition, the Box-Behnken Design (BBD) strategy was adopted to optimize the detection conditions and greatly reduce experimental errors. Under optimized conditions, the tetracycline concentration detected by the sensor had a linear relationship with the impedance in the range of 0.1–105 nM TC. The lowest detection limit was 0.01 nM. NH2-MIL-101(Fe)/CNF electrospinning aptasensor exhibited good selectivity and stability. Furthermore, quantitative detection of tetracycline was achieved in real water samples. The sensor reported here could become a promising new strategy for detecting tetracycline in environmental water samples in the future.

General fabrication of metal-organic frameworks on electrospun modified carbon nanofibers for high-performance asymmetric supercapacitors

Metal-organic framework (MOF)-based electrode materials have become a hot subject for supercapaitors. Herein, Ni-MOFs grown on Co nanoparticles modified carbon nanofibers (CNFs) (C-Co@MOF) are prepared via a facile process. Interestingly, the presence of Co nanoparticles in CNFs not only boosts the hybridization of CNF and MOFs, but also releases Co ions to participate in the growth of MOF, leading to a favorable electrochemical behavior. In detail, the specific capacitance of C-Co@MOF reaches 1201.6 F g−1 that exceeds those of C-M@MOFs (M = Ni, V, Mo, Mn, Fe, Cu and Zn) and CNF@MOF. More importantly, an asymmetric solid-state supercapacitor is assembled using C-Co@MOF and nitrogen-doped carbon nanotubes derived from polyaniline as positive and negative electrode materials, respectively, representing a high energy density of 37.0 Wh kg−1 and outstanding durability. This work highlights the superiority of electrospun CNFs modified by metal nanoparticles for the growth of MOF, showing great potential for electrochemical energy storage and conversion applications.

Electrochemical detection of ascorbic acid with chemically functionalized carbon nanofiber/β-cyclodextrin composite

We modified carbon nanofiber (CNF) with chemical oxidation method and functionalized with β-cyclodextrin (βCD) as for the electrochemical detection of ascorbic acid. Chemical oxidation introduced new hydrophilic oxygen functional groups into CNF, resulting that wettability, dispersion and reactivity are enhanced. Furthermore, it has increased the functionalization of βCD over oxidized CNF surface. As a result, synthesized electrode showed high sensitivity (0.1 µA/µM) and excellent selectivity with low detection limit (0.9 µM) in the detection of ascorbic acid. The simple chemical oxidation of CNF followed by the functionalization with βCD resulted excellent electrochemical performance in the detection of ascorbic acid.

Surface modified carbon nanomats provide cationic and anionic rectifier membranes in aqueous electrolyte media

Carbon nanofibers (CNFs) are converted into anionic current rectifiers by surface modification with amine functional groups using hydrothermal means (forming modified CNFs, with generation-3 poly (propylene imine) dendrimer, urea and boric acid). To confirm surface charge, morphological changes and carbon nanomat thickness, zeta potential analysis, transmission electron microscopy (TEM) and scanning electron microscopy (SEM), were used. When a dispersion of surface modified carbon nanofibers in DMF is drop-cast asymmetrically to form nanomats onto laser drilled microholes (5, 10, or 20 µm diameter) of poly (ethylene terephthalate) substrates and immersed into aqueous electrolyte solutions, anionic diode behaviour is observed (in contrast to pristine carbon nanofibers, which exhibit cationic diode behaviour). The effects of electrolyte type, ionic strength, and microhole diameter on ionic diode performance were investigated using cyclic voltammetry, chronoamperometry, and impedance spectroscopy. Future applications in desalination are proposed.