Decorated Carbon Nanofibers Research Articles

Fe2P nanoparticle-decorated carbon nanofiber composite towards lightweight and highly efficient microwave absorption.

An Fe2P nanoparticle (Fe2P NP)-decorated carbon nanofiber (represented as Fe2P@CNF) composite was in situ prepared by electrospinning and subsequent high-temperature treatment. Benefitting from the synergy effect between Fe2P NPs and CNFs, as well as improved interface polarization and impedance matching, the Fe2P@CNF composite exhibits excellent microwave absorption performance relative to pure CNFs, in which the Fe2P@CNF composite with a fill loading of only 10 wt% possesses a minimum reflection loss (RL) of -49.2 dB at 3.0 mm and a maximum effective absorption bandwidth of 6.0 GHz at 2.2 mm. Therefore, this work provides a promising approach for the design and synthesis of an Fe2P@CNF composite with high-performance microwave absorption.

Atomic Dual‐Site Ni/Co‐Decorated Carbon Nanofiber Paper for Efficient O2 Electrocatalysis and Flexible Zn‐Air Battery

AbstractThe fabrication of flexible catalytic films with isolated single/dual‐atomic sites and their integration in wearable electronics is challenging. Herein, an efficient method to prepare atomically dispersed binary Ni/Co‐decorated flexible carbon nanofiber (NiCo‐CNF) film using formamide‐derived cyano‐specific NiCo‐NC as nanofillers was developed. The optimized Ni1Co1‐CNF catalytic film, having large‐area, high density of adjacent Ni‐N4 and Co‐N4 active sites, and good mechanical properties under repeated bending and release conditions, possessed high catalytic activity towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The ORR/OER potential difference (ΔE10) for Ni1Co1‐CNF at 10.0 mA cm−2 was highly comparable with the Pt/C+RuO2 mixture. In addition, flexible Ni1Co1‐CNF‐assembled Zn‐air battery displayed very good mechanical robustness and cycling stability. Our work may inspire the fabrication of other atomic metal‐decorated films for membrane electrocatalysis.

Integrated electrochemical and photocatalytic degradation using ZnO caterpillars photocatalyst: Two-step approach for textile industry based wastewater recovery

A wide range of synthetic dyes released by the textile industry endangers human and environmental health. Even trace amounts of synthetic dye in water are easily visible and toxic to human health. Therefore, there is a burgeoning need for innovative treatment techniques that can result in the destruction of dye molecules in wastewater. This work aims at developing two-step processes for treating textile wastewater before discharging them into nature waterbodies. The step includes the electrochemical processing of the real sample, followed by the real time photocatalytic degradation using novel ZnO caterpillars. A facile fabrication approach is used to produce a ZnO caterpillar over SiO2/Si wafer using a vapor–liquid-solid (VLS) method, where gold nanoparticles (Au NPs)-decorated carbon nanofibers were used as catalyst providers. These ZnO caterpillars have been well characterized using techniques such as scanning electron microscope, X-ray diffraction, Raman spectroscopy, and contact angle goniometer. The contact angle results show the shifts of contact angle from 78.85˚ to 130.35˚ for pure SiO2/Si wafer and ZnO caterpillar-SiO2/Si leading to a hydrophobic surface. It was confirmed that with ZnO caterpillars, a photocatalytic response of ∼ 240 min for completely degrading electrochemically treated textile wastewater under UV light exposure was recorded. During this study, real-time textile wastewater degradation is monitored using the IoT technique by integrating a NodeMCU microcontroller board as a control center and a pH sensor as a tool for detecting the change in pH value of the textile wastewater under UV light exposure.

Fabrication of heterojunction MnTiO3–TiO2-decorated carbon nanofibers via electrospinning as an effective multifunctional photocatalyst

Abstract In this paper, we successfully synthesized heterojunction manganese titanate/titanate nanoparticles (MnTiO3–TiO2 NPs)-decorated carbon nanofibers (CNFs) employing the electrospinning process. The morphology, crystallinity, and chemical composition of the MnTiO3/TiO2-decorated CNFs is characterized via SEM, FESEM, STEM, TEM EDX, and XRD techniques. The synthesized nanocomposite exhibits good performance for photodegradation of methylene blue (MB) dye and hydrolysis of ammonia–borane complex for hydrogen releasing experiment in a batch reactor under visible light. A mathematical model was developed to predict the photocatalytic activity of the produced nanocomposite with various parameters. The operational parameters include the effect of the initial concentration, catalyst dosage, light intensity, and reaction temperature, which are studied to validate the mathematical model. The reaction rate constant of MB photodegradation is found to be 0.0153 min−1 for an initial MB concentration of 5 mg·L−1 with a catalytic dosage of 200 mg·L−1 at a reaction temperature of 25°C under a light intensity of 25 W·m−2. Similarly, the H2 generation employing TiO2@CNFs and MnTiO3/TiO2@CNFs under visible light irradiation is observed to be 0.31 mol and 2.95 mol, respectively, corresponding to an exposure of 10 min. We also demonstrated that the yield of hydrogen employing MnTiO3/TiO2@CNFs under visible light increases to 2.95 mol compared with 1.51 mol in darkness. Finally, comparisons were made between the experimental and model-predicted values of the reaction rate constant and final concentrations. Theoretical and experimental data of photocatalytic activity are found to be in good agreement for MnTiO3/TiO2@CNFs.

Cobalt-decorated carbon nanofibers as a low overpotential cathode for nonaqueous Na-CO2 batteries

As the high energy-density energy storage and greenhouse gas capture device, Na-CO2 battery development is impeded by the sluggish CO2 reduction and difficult decomposition of insulating discharge products on the cathode. Here, the cobalt (Co)-decorated carbon nanofibers accompanying with slight Co oxidation were used as the self-standing cathode for Na-CO2 battery. It greatly reduces the discharge overpotential by 500 mV and charge overpotential by 210 mV, delivers a 12 times higher discharge capacity and runs nearly 4 times cycle life than its counterpart. Experiment combined with theory calculation demonstrates that the evenly dispersive, abundant and stable active sites (Co-CoO) with an equal CO2 adsorption-desorption capability is the key to improving cell performance. This work reveals the importance of catalysts/cathodes and provides a direction to design highly efficient catalysts/cathodes for alkali metal-CO2 batteries.

Fluorinated bimetallic nanoparticles decorated carbon nanofibers as highly active and durable oxygen electrocatalyst for fuel cells

The low activity and durability are still the critical barriers for non-precious metal electrocatalyst, mainly involving M-N/C (M = Fe, Co, Mn et al), applied in fuel cell. Constructing bimetallic sites has been explored as an effective method to boost the performance of the catalyst for the synergistic effect between metal atoms. However, this synergistic effect is always suppressed in acidic conditions and results in unstable catalytic performance. Here we create novel fluorinated iron (Fe) and cobalt (Co) bimetallic nanoparticles distributed on nitrogen-doped carbon nanofibers (CNFs) for oxygen reduction reaction (ORR). The fluorination strongly increased the charge density of the bimetallic catalyst and resulted in a remarkable catalytic performance with the half-wave potential of 804 mV in 0.1 M HClO4 and 1.6 times power density improvement for the proton exchange membrane fuel cell device. Importantly, the chemical and mechanical robust CNFs support improved the electric conductivity and stability of bimetallic catalysts, which leads to an ultra-stable electrocatalyst. The fuel cell voltage can keep stable even after 110 h, instead of the continuingly decrease in the traditional M-N/C.

Synthesis, characterization and mechanism of electrospun carbon nanofibers decorated with ZnO nanoparticles for flexible ammonia gas sensors at room temperature

A flexible gas sensor based on ZnO nanoparticles decorated carbon nanofibers (ZnO@CNF) was fabricated by electrospinning, preoxidation, oxidation and carbonization to detect ammonia at room temperature. SEM, TEM, EDS, XPS, XRD and Raman spectra were used to analyze the morphology, structure and composition of the composite. By using electrospinning technology, preoxidation at 220 °C in air, oxidation at 410 °C and carbonization at 600 °C in argon, ZnO@CNF with a diameter of about 200 nm were synthesized. The preoxidation stage includes cyclization, dehydrogenation and oxidation of PAN, while the carbonization was contributed to the decreasing of carbon nanofiber diameter. The gas sensing test results show that ZnO@CNF has higher response, better selectivity than CNF to ammonia at room temperature, while greatly reducing the optimum working temperature of pure ZnO. The flexibility test of ZnO@CNF shows that the composite of metal oxides and carbon materials has a certain degree of flexibility. With the advantages of flexibility, room temperature operation and good response to ammonia, gas sensors based on ZnO@CNF are expected to become a potential candidate for the detection of ammonia in exhaled gas of patients with gastrointestinal diseases or kidney diseases in the future.

V2O3-decorated carbon nanofibers as a robust interlayer for long-lived, high-performance, room-temperature sodium–sulfur batteries

We developed a V2O3 nanoparticle–decorated carbon nanofiber (V2O3@CNF) interlayer for room-temperature sodium–sulfur batteries (RT/NaSBs), inserted on the cathode side of the separator to inhibit the shuttling of sodium polysulfides, i.e., their migration to the sodium anode, and thus realize high-performance RT/NaSBs. The V2O3 adsorbs polysulfides and catalytically promotes polysulfide trapping, while the CNFs provide conductive channels that facilitate ion transport and accelerate reaction kinetics. The electrochemical performance of the resulting Na–S cells are superior to those of cells with a CNF interlayer and without an interlayer. A cell with a V2O3@CNF interlayer utilizes almost 70% of its active material at 0.1C, while cells with a CNF interlayer and without an interlayer utilize 54 and 33%, respectively. It demonstrates superior rate performance, achieving a capacity of 268 mA h g−1 at 2.0C, and its diffusion coefficient (∼10−11cm2 s−1) is an order of magnitude higher than those of cells with a CNF interlayer or without an interlayer (∼10−12 cm2 s−1), indicating fast reaction kinetics. Moreover, it delivers a discharge capacity of 406 mA h g−1 after 500 cycles at 1.0C with a high coulombic efficiency of 100%. Even at a high C-rate of 2.0C, the capacity of the cell decays at a low rate of 0.076% per cycle over 1000 cycles, indicating exceptional capacity retention. The outstanding electrochemical performance is mainly attributed to the effective sodium polysulfide confinement, improved active material utilization, and accelerated reaction kinetics associated with the V2O3@CNF interlayer.

Rational design of CdCO3 nanoparticles decorated carbon nanofibers for boosting electrochemical CO2 reduction

Efficient, robust and inexpensive catalysts are highly desirable to drive the electrochemical CO2 reduction reaction (CO2RR) to value-added fuels. Herein, low-cost CdCO3 nanoparticles (NPs) decorated carbon nanofibers (CdCO3-CNFs) were synthesized by a facile one-pot method to boost the performance of CO2RR to CO. The obtained CdCO3-CNFs show a high Faradaic efficiency (93.4%) and a good partial current density (~10 mA cm−2) at a potential of −0.83 V. Moreover, CdCO3-CNFs achieve high CO production rates at moderately negative potentials and a good stability of 24 h with negligible degradation. The superior performance is attributed to the increased number of catalytically active sites, and the strong interaction between CdCO3 NPs and CNFs which promotes electron transfer and secures active sites. This study provides a promising strategy for the efficient and durable CO2RR by designing a carbonate/carbon system with a strong catalyst-support interaction.

Metal oxide heterostructure decorated carbon nanofiber as a novel redox catalyst for high performance Lithium-Sulfur batteries

Lithium-sulfur batteries (LSBs) are the promising next-generation energy storage devices; however, the uncontrolled shuttle effect and sluggish redox kinetics severely hinder their commercial success. To solve these barriers, herein, a heterostructure constructed from CoFe2O4 and SnO2 decorated over the carbon nanofiber framework (CoFe@SnCNF) is reported as a sulfur redox catalyst in the cathode of LSB. A synergism between the multiple adsorptive and catalytic sites of the heterostructure enables an efficient lithium polysulfide (LiPS) entrapment and expedites their conversion, meanwhile the carbon nanofiber framework provides a long-range electrical conduction. Based on these merits, the CoFe@SnCNF integrated sulfur cathode with an areal sulfur loading of ~ 2.2 mg cm−2 retained 71.1 % of initial capacity after 100 cycles at 0.2 C, and showed excellent cyclability with a capacity fading rate of only 0.11 % over 200 cycles at 0.5 C. Even under a raised sulfur loading of 5.3 mg cm−2, the cathode still showed an impressive performance with an initial capacity of 442.3 mAh g−1 that retained 78.1 % after 80 cycles. The findings of this work shed light on the feasibility for further development of novel heterostructure by synergistically coupling various polysulfide adsorbing and catalyzing materials.

Decoration of carbon nanofibers with bimetal sulfides as interlayer for high performance lithium-sulfur battery

In order to obtain high-performance lithium-sulfur (Li-S) batteries, the rapid capacity loss caused by the notorious polysulfide shuttle effect is an urgent challenge to be solved. It is widely reported that polysulfides are trapped in electrolytes due to the strong chemisorption of polar materials in Li-S batteries. Here, a free-standing NiCo2S4 nanoparticles decorated carbon nanofibers (NiCo2S4-CNFs) interlayer is prepared via electrospinning and simple hydrothermal method for the application in Li-S batteries. Three-dimensional carbon fibers (CNFs) skeleton builds a highly conductive carbon network, which provides a large quantities of transmission paths for electrons and ions. Uniformly distributed NiCo2S4 nanoparticles act as an absorbent of the long-chain lithium polysulfides (LiPSs) and a catalyst to accelerate the conversion of sulfur species. Meticulous designed NiCo2S4-CNFs interlayer significantly improves the capacity retention rate and cycle stability of Li-S batteries. It supplies an initial specific capacity of 1421 mAh g−1 at 0.1 C, and its capacity remains at 918 mAh g−1 after 200 cycles at 0.2 C. Even at a high current density of 1 C, it still possesses a reversible specific capacity of 515 mAh g−1 after 500 cycles and extremely low capacity decay of 0.06% per cycle. More importantly, the NiCo2S4-CNFs interlayer still delivers excellent electrochemical performance with a higher sulfur loading of 4.5 mg cm−2, which verifies its huge commercial application potential.

Hydrothermal Synthesis of Ce-doped ZnO Heterojunction Supported on Carbon Nanofibers with High Visible Light Photocatalytic Activity

Ce/ZnO decorated carbon nanofibers(CNFs) heteroarchitectures(Ce/ZnO/CNFs) have been synthesized using electrospinning technique followed hydrothermal method, which have a high visible light photocatalytic activity. The samples were characterized by means of SEM, FTIR and XRD. The photocatalytic performance of Ce/ZnO/CNFs was tested with the methylene blue in the presence of visible light irradiation. In this work, we have analyzed the effects of Ce doping amount, initial methylene blue(MB) concentration and dosage of Ce/ZnO/CNFs on photocatalytic efficiency of the composite. The results showed that the photocatalyst containing 1.0% Ce in molarity(CZC1) obtained by autoclaving at 150 °C has the best photocatalytic degradation of MB than other as-synthesized samples. Ce/ZnO/CNFs catalysts exhibit a good stability and reusability, which would be an economical and environmentally friendly photocatalyst for various practical applications.

3D Prussian blue/Pt decorated carbon nanofibers based screen-printed microchips for the ultrasensitive hydroquinone biosensing

Nowadays, water pollution has become more serious, greatly affecting human life and healthy. Electrochemical biosensor, a novel and rapid detection technique, plays an important role in the real-time and trace detection of water pollutants. However, the stability and sensitivity of electrochemical biosensors remain a great challenge for practical detections in real samples to the strong interferences derived from complex components and coagulation effects. In this work, we reported a novel three-dimensional architecture of Prussian blue nanoparticles (PBNPs)/ Pt nanoparticles (PtNPs) composite film, using 3D interweaved carbon nanofibers as a supporting matrix, for the construction of screen-printed microchips-based biosensor. PtNPs with diameters of ~2.5 nm was highly dispersed on the carbon nanofibers (CNFs) to build a 3D skeleton nanostructure through a solvothermal reduction. Subsequently, uniform PBNPs were in-situ self-assembled on this skeleton to construct a 3D architecture of PB/Pt-CNF composite film. Due to the synergistic effects derived from this special feature, the as-prepared hydroquinone (HQ) biosensor chips can synchronously promote both surface area and conductivity to greatly enhance the electrocatalysis from enzymatic reaction. This biosensor has exhibited a high sensitivity of 220.28 μA·L·mmol−1·cm−2 with an ultrawide linear range from 2.5 μmol·L−1 to 1.45 mmol·L−1 at a low potential of 0.15 V, as well as the satisfactory reproducibility and usage stability. Besides, its accuracy was also verified in the assays of real water samples. It is highly expected that the 3D PB/Pt-CNF based screen-printed microchips will have wide applications in dynamic monitoring and early warning of analytes in the various practical fields.

Electroanalytical detection of amlodipine in urine and pharmaceutical samples using Ag-Ce2(WO4)3@CNF nanocomposite-modified glassy carbon electrode

A novel, simple, and convenient electroanalytical method for the detection of Amlodipine (AMD) has been investigated via an electro-oxidation mechanism using silver-cerium tungstate decorated carbon nanofiber (Ag-Ce2(WO4)3@CNF) nanocomposite by differential pulse voltammetry (DPV) for the first time. Ag-doped Ce2(WO4)3 decorated CNF was constructed by using simple hydrothermal followed by ultrasonication methods. The synthesized ternary nanocomposite was characterized by using FT-IR, X-Ray Diffraction, Raman spectroscopy, SEM with EDX, and TEM analysis. The Ag-Ce2(WO4)3@CNF modified GCE shows an excellent electrocatalytic response towards the oxidation of AMD in 0.05 M of PBS (pH 7) compared to Ag and Ag-Ce2(WO4)3 modified electrodes. The AMD detection limit is found to be 0.712 nM with a linear range of 0.01–130 μM. The electrocatalytic property of the ternary nanocomposite of electrochemical sensing of AMD in different real samples (human urine and pharmaceutical drug) has been investigated and achieved tremendous recovery. The fabricated sensor also shows good selectivity, reproducibility, and long-time stability. Hence, this ternary nanocomposite could be open a new platform in biomedical applications.

Fabrication of Carbon Nanofibers Decorated with Various Kinds of Metal Oxides for Battery Applications

Carbon nanofibers decorated with various metal oxide nanoparticles were fabricated by combining an electrospinning technique of bicomponent polymer mixture and a sol-gel reaction and subsequent carbonization process. Electrospun polymer nanofibers consisting of polyacrylonitrile (PAN) and poly(vinyl pyrrolidone) (PVP) with controllable diameters were fabricated with PAN/PVP core/shell types via phase-separation due to the immiscibility between two polymers. The electrospun nanofibers served as supporting materials with binding sites of PVP to incorporate titanium oxide precursor. Subsequently, the carbonization of the fibers led to the formation of carbon nanofibers@TiO2 for energy application, in which rutile TiO2 nanoparticles were decorated on the surface of carbon nanofiber. Especially, this TiO2 decorated carbon nanofiber electrode exhibited excellent electrochemical property in lithium-ion batteries (≈600 mA h g−1 at C/5 rate for 100 cycles). Furthermore, the carbon nanofibers were also successfully modified with other metal oxides, including NiO, SnO2, and ZrO2 nanoparticles, in a similar manner.

Decorated carbon nanofibers with mixed nickel−manganese carbides for methanol electro-oxidation in alkaline solution

Transition metal carbides were recently investigated in many vital applications due to their satisfactory thermal, mechanical and chemical characteristics. They showed a metallic architecture of the host lattice containing interstitial voids of carbon atoms. In this work, mixed nickel-manganese carbides were synthesized onto carbon nanofibers [NiC–MnC@CNFs] in different proportions using the electrospinning process with subsequent calcination at 800 °C. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were employed to physically characterize the prepared nanomaterials. Homogeneous distribution of nanometallic particles over CNFs was clearly observed in SEM images. XRD charts detected the formation of mixed metallic carbides of Ni0.98C0.02 and (Mn9C)0.4 formulations in different nanomaterials. Excellent electrocatalytic behavior was displayed by NiC–MnC@CNFs nanocatalysts when methanol molecules were introduced into the alkaline solution. Methanol oxidation current density of 110.34 mA cm−2 was measured at the nanomaterial containing NiAc:MnAc ratio of 90:10 with a lowered Eonset value of 310 mV (Ag/AgCl). The effect of varying methanol concentration and the scan rate during the electro-oxidation reaction on the resultant nanomaterial activity was studied. Moreover, the feasibility of charge transfer step was significantly affected by the chosen potential value. Highly pronounced rate was measured at 450 mV. The chronoamperometric study revealed a promising stability trend with increased steady state oxidation current densities especially at nanopowders with lowered MnAc wt.%. The synergistic effect between mixed metallic carbides and CNFs could account for the improved electrocatalytic properties towards methanol molecules oxidation.

Morphology-controlled fabrication of NiCo2S4 nanostructures decorating carbon nanofibers as low-cost counter electrode for efficient dye-sensitized solar cells

The development of highly efficient, earth-abundant and low-cost counter electrode materials is of significant importance and challenge for practical application in dye-sensitized solar cells. In this work, morphology-controlled NiCo2S4 nanoparticles (NPs) and nanorods (NRs) decorating carbon nanofibers (CNFs) have been prepared via an electrospinning and hydrothermal or solvothermal strategy, which are further utilized as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). Benefitting from the rich nickel and cobalt ions redox chemistry and more exposed catalytically active sites from NiCo2S4 NRs grown vertically on the surface of CNFs as well as faster electron transporting capability providing by the highly conductive CNFs, the DSSC device based on NiCo2S4 NRs/CNFs CE yields an excellent power conversion efficiency of 9.47%, which is higher than that of the devices with NiCo2S4 NPs/CNFs (8.63%), Pt (8.18%) and CNFs (6.06%) as CEs under AM 1.5 G irradiation. Furthermore, the NiCo2S4 NRs/CNFs CE shows an excellent electrochemical stability in an iodine-based electrolyte. This study highlights a controllable and versatile route to rational design efficient counter electrode catalysts for high-performance CEs application.

Nanoneedle-like NiCo2O4 Decorated Carbon Nanofiber Electrodes for Supercapacitors

Flexible electrodes based on carbon fiber with excellent conductivity were utilized in supercapacitor applications. Herein, the nanostuctured NiCo2O4 was synthesized along the nanofibers by a brief hydrothermal method. As-prepared NiCo2O4/CNF composite holds unique structure with NiCo2O4 nanoneedles uniformly grown on every carbon nanofiber, which promised shorter diffusion of electrons and ions. The composite electrode held a high capacitance of 660.41 F g−1 and showed great capacitance retention of 90.95% after 6000 cycles, which could be beneficial in future application of supercapacitors.

Flexible and Superhydrophobic Composites with Dual Polymer Nanofiber and Carbon Nanofiber Network for High-Performance Chemical Vapor Sensing and Oil/Water Separation.

Polymer nanofiber composites with superhydrophobicity are promising for the chemical vapor sensing or oil/water separation, but it remains challenging to develop superhydrophobic, anticorrosive, and durable nanofiber composites that can achieve both the organic solvent vapor detection and oil (organic solvent)/water separation with high separation flux and excellent recyclability. Here, a flexible, stretchable, and superhydrophobic/superoleophilic nanofiber composite membrane with excellent photothermal conversion performance is fabricated by decorating carbon nanofibers (CNFs) with a hollow structure onto the polyurethane nanofibers and subsequent polydimethylsiloxane (PDMS) modification. The combination of CNFs and PDMS greatly improves the membrane's tensile strength and Young's modulus without sacrificing its stretchability. The dual polymer nanofiber and CNF network are beneficial to the chemical vapor or liquid diffusion into the membrane and thus can be used for high-performance chemical vapor sensing and oil/water separation. The nanofiber composite is responsive to different organic vapors with a low detection limit and good selectivity. Also, the material can achieve fast oil/water separation with the oil (dichloromethane) permeate flux as high as 6577.3 L m-2 h-1. In addition, the separation flux and efficiency remain stable during the 30 separated oil/water separation tests, exhibiting excellent recyclability.

Mn2O3 nanoflower decorated electrospun carbon nanofibers for efficient hybrid capacitive deionization

Developing highly efficient electrochemical desalination techniques with both high salt removal capacity as well as sufficient longterm durability is urgently required in settling the global water crisis. Herein, we developed a high-performance hybrid capacitive deionization (HCDI) through the deployment of freestanding, Mn2O3 nanoflower decorated carbon nanofibers (CNF@Mn2O3) with pseudo-capacitive behavior as the electrode. The CNF@Mn2O3 synthesized via electrospinning and in-situ deposition of Mn2O3 shows both excellent pseudo-capacitive performance and freestanding nanostructure, which enables the CNF@Mn2O3-based HCDI system to exhibit superior desalination performance(27.43 mg∙g−1) as well as long-term stability (14.3% declination for 30 cycles). Such outstanding desalination performance should be ascribed to the high pseudo-capacitance, excellent charge transfer performance, and the freestanding nature of the CNF@Mn2O3. This study is interesting because it exemplifies the importance of designing pseudo-capacitive electrode materials for constructing a high-performance HCDI system, which could cast light on the further development of high-efficiency electrochemical desalination systems.