Carbon Cloth Substrate Research Articles

Enhancing electrode efficiency by tuning surface electronic properties and defects in NiFe layered double hydroxide nanosheets with Al or Zn cation vacancies

Layered double hydroxides (LDHs) containing transition metals have emerged as promising electrode materials for supercapacitors due to their low cost, strong redox activity, and environmental friendliness. In this study, we propose a novel approach by creating Zn-defect Zn(II) engineered D-NiFeZn-LDHs through cyclic voltammetry etching in an alkaline solution of NiFeZn-LDHs synthesized on a carbon cloth substrate. This defect engineering increases electrochemical active sites and improves ion diffusion within the layered structure. The D-NiFeZn-LDHs demonstrate an impressive specific capacitance of 1204.8 F g⁻1 at 1 A g⁻1 and retain 61.52 % of their initial capacity after 10,000 cycles at 10A g⁻1, showcasing excellent long-term cycling stability. Moreover, the all-solid-state asymmetric supercapacitor constructed using D-NiFeZn-LDHs delivers a high energy density of 31.63 Wh kg⁻1 at 125 W kg⁻1 and retains 65.95 % of its capacity after 5000 cycles at a high current density of 10 A g⁻1. These findings provide a new strategy for developing high-performance energy storage materials.

Carbon dots modified hydrange-shaped ZnCo(OH)F used as a flexible electrode for sensitive detection of dopamine and uric acid

Dopamine (DA), widely recognized as the most prevalent catecholamine neurotransmitter in the brain, functions as a vital regulator of various physiological processes within the central nervous system. Meanwhile, uric acid (UA) serves as the terminal product of purine metabolism, and hyperuricemia emerges as a significant risk factor for gout, with a steep escalation in risk as blood uric acid levels surge. Consequently, monitoring the concentrations of DA and UA in biological fluids is crucial not only for the treatment of related disorders but also for enhancing disease prevention strategies. In this work, the blooming hydrangea shaped ZnCo(OH)F/carbon dots (CDs) composite was grown on carbon cloth (CC) substrate by a simple hydrothermal method, which was used as a flexible sensor for the detection of DA and UA. The unique open structure and morphologic adjustment strategy of ZnCo(OH)F/CDs/CC provided a large surface area and highly exposed active site. After screening the experimental variables that affect the sensor performance, the optimal ZnCo(OH)F/CDs/CC flexible electrode achieved individual and simultaneous detection for DA and UA in the concentration ranges of 1.0220.0µM and 1.0500.0µM, the detection limits (LOD) of DA and UA were 0.0129 and 0.044μM, respectively (S/N=3). In addition, the sensor exhibited good repeatability, stability and selectivity, realizing the detection of DA and UA in human serum with recovery rate of 95.20% 105.3%. Also, the density functional theory (DFT) calculations were used to explore the interaction between electrode material and detected substrate. A simple hydrothermal method was utilized to grow the ZnCo(OH)F/CDs composite onto the CC substrate. The presence of F− in ZnCo(OH)F can increase the charge mobility and improve the conductivity. ZnCo(OH)F/CDs/CC as flexible electrode material can determine DA and UA simultaneously in human serum with a satisfactory recovery rate. This flexible sensor has a broad application prospect in the manufacture of wearable devices.

Investigation of efficient adsorption-electrochemical degradation performance of ZIF-8/MWCNTs nanocomposites toward 2,4-dichlorophenol

The highly toxic and recalcitrant organic pollutant, 2,4-dichlorophenol (2,4-DCP), is commonly found in wastewater. Therefore, it is critical to investigate novel techniques for the efficient removal of 2,4-DCP from wastewater. The present study employed a one-step synthesis method to fabricate ZIF-8/multi-walled carbon nanotubes (ZIF-8/MWCNTs) nanocomposites with well-defined mesoporous structures, which were subsequently coated onto carbon cloth (CC) to form the anode ZIF-8/MWCNTs/CC. Subsequently, the adsorption performance of ZIF-8/MWCNTs toward 2,4-DCP and the adsorption-electrochemical degradation performance of ZIF-8/MWCNTs/CC toward 2,4-DCP were investigated. ZIF-8/MWCNTs exhibit exceptional adsorption capacity and rate toward the 2,4-DCP. At 303 K, it achieved a saturated adsorption amount as high as 1056.78 mg·g−1 within only 30 min of reaching equilibrium. Moreover, when coated on CC substrates, the internal pore structure of ZIF-8/MWCNTs is effectively exploited during the adsorption. In addition, the incorporation of MWCNTs enhances the conductivity of the ZIF-8/MWCNTs/CC electrodes, leading to reduced resistance and improved electron transfer rate. Notably, ZIF-8/MWCNTs/CC enabled complete removal of a 25 mg·L-1 solution of 2,4-DCP within only 90 min and a 50 mg · L-1 solution within 120 min. Furthermore, the degradation mechanism of 2,4-DCP was analyzed by means of DFT modeling theoretical calculations and intermediate product determination analysis, while evaluating the toxicity of the generated material was evaluated. This study provides improved solutions and strategies for the treatment of chlorophenolic compound pollution in wastewater.

Prussian Blue-Derived Atomic Fe/Fe3C@N-Doped C Catalysts Supported by Carbon Cloth as Integrated Air Cathode for Flexible Zn-Air Batteries.

The development of an integrated air cathode with superior oxygen reduction reaction (ORR) performance is fundamental to flexible zinc-air batteries (ZABs) for wearable electronics. Herein, a self-assembled metal-organic framework (MOF)-derived strategy is proposed to prepare a atomic Fe/Fe3C@N-doped C catalysts supported by carbon cloth (CC) catalyst for use as an air cathode of flexible ZABs. The Prussian Blue precursor, which self-assembles on the surface of the carbon cloth due to electrostatic attraction, is critical in achieving the uniform dispersion of catalysts with high density loading on carbon cloth substrates. The hollow cubic structure, N-doped carbon layer coating, and the integrated electrode design can provide more accessible active sites and facilitate a rapid electron transfer and mass transport. Density functional theory (DFT) calculation reveals that the electronic interactions between the Fe-N4 and Fe3C dual active sites can optimize the adsorption-desorption behavior of oxygen intermediates formed during the ORR. Consequently, the Fe/Fe3C@N-doped C/CC exhibits an excellent half wave potential (E1/2 = 0.903V) and superior long-term cycling stability in alkaline environments. With excellent ORR performance, ZABs and flexible ZABs based on Fe/Fe3C@N-doped C/CC air cathode demonstrate excellent overall electrochemical performance in terms of open circuit voltage, maximum power density, flexibility, and cycling stability.

Modulating NFO@N‐MWCNTs/CC Interfaces to Construct Multilevel Synergistic Sites (Ni/Fe‐O‐N‐C) for Multi‐Heavy Metal Ions Sensing

AbstractA hierarchical heterogeneous composite electrode of NiFe2O4@nitrogen‐doped multi‐walled carbon nanotubes/carbon cloth (NFO@N‐MWCNTs/CC) is prepared via a dip‐coating method, followed by a hydrothermal process. The flexible carbon cloth (CC) substrate provides robust support and the cross‐linked nitrogen‐doped multi‐walled carbon nanotubes (N‐MWCNTs) on the CC form a highly porous network with a large specific area that facilitates electron‐transfer. The stable support strengthens the framework and prevents pore structure disorder within the porous network, that could lead to the structural instability of the active sites. The decorated NiFe2O4 nanoparticles offer abundant active sites for enhanced electrocatalytic activity. Benefiting from the synergistic effect of the 3D hierarchical heterogeneous microstructure and multilevel bimetallic oxide active site (Ni/Fe‐O‐N‐C) constructs, the NFO@N‐MWCNTs/CC electrode achieves stable detection of multiple heavy metal ions (HMIs) with high reproducibility. The modified electrode allowed stable detection of multiple heavy metal ions with high reproducibility. The sensitivities of the electrode for Cd(II), Pb(II), Bi(III), and Hg(II) are 344.98, 441.02, 176.484, and 371.099 µA µm−1, respectively. The assay recoveries ranged from 95.3% to 106.8%, highlighting its practical applicability. This study provides innovative composites and theoretical insights to facilitate further advances in the simultaneous high‐performance detection of heavy metal ions.

Performance-tunable thermal barrier coating for carbon fiber-reinforced plastic composites via flame spraying

Thermal barrier coatings (TBCs) are essential for improving the heat resistance of materials operating in high-temperature environments. This paper proposes a new method for manufacturing double-layered TBC with graded porosity for carbon fiber-reinforced plastic (CFRP) composites. The TBC was created by a flame spraying process, consisting of relatively dense and porous layers: (1) a dense layer was produced by spraying yttria-stabilized zirconia (YSZ) particles directly onto neat carbon fabric substrate and (2) a porous layer was prepared by co-spraying YSZ particles with sacrificial polyetheretherketone (PEEK) particles. The porosity of the porous layer was controlled by varying a PEEK injection distance (D) and a PEEK feed rate (R). The correlation between porosity and thermal conductivity of the TBC layer was investigated to assess its thermal barrier performance. The TBC fabricated with the D = 5 cm and the R = 1.0 g/min offered the optimal porosity and conductivity. The 640μm-thick TBC with 34% porosity and 0.27 W/m·K thermal conductivity protected the CFRP substrate remarkably under the subjected torch at 500°C, as the TBC layer reduced the surface temperature of CFRP to 230°C. Thermomechanical analysis, following thermal shock tests, revealed that the double-layered TBC/CFRP composite retained 87% and 75% of its pristine flexural strength and modulus, respectively, while the neat CFRP composite was completely burnt out. This study explored the application of flame spray technology to develop highly effective double-layered TBCs with tunable porosity to maximize their thermal barrier performances. All results from the current study provide new insights into the design and development of TBC and CFRP composites, which will benefit a wide range of lightweight high-temperature applications.

Deliberate Amorphization of Co-MOF for Constructing Crystalline-Amorphous Heterostructures Toward High-Performance Water Electrolysis.

The endowment of metal organic frameworks (MOF) with superior electrocatalytic performance without compromising their structural/compositional superiorities is of great significance for the development of renewable energy devices, yet remains a grand challenge. Herein, a deliberate partial amorphization strategy is developed to construct a heterostructured electrocatalyst consisting of crystalline Co-MOF and amorphous Co-S nanoflake arrays aligned on the carbon cloth (CC) substrate (abbreviated as Co-MOF/Co-S@CC hereafter) through a rapid sulfuration method. The simultaneous implement of crystalline-amorphous (c-a) heterostructure and nanoflake arrayed architecture on CC substrate renders the Co-MOF/Co-S@CC with abundant and tight active sites, accelerated charge transfer rate, regulated electronic structures, and reinforced structural stability. As such, the obtained Co-MOF/Co-S@CC electrode demonstrates outstanding electrochemical hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances with the overpotentials of 64 and 217mV at 10mA cm-2, respectively. Moreover, a two-electrode electrolyzer assembled by Co-MOF/Co-S@CC electrodes exhibits the lower cell voltages and larger current densities than those of Pt/C and RuO2 counterparts, excellent reversibility and prominent long-term stability, representing a great prospect for feasible H2 production. This adopted concept of c-a heterostructure for electronic regulation may bring about insightful inspiration for designing high-performance electrocatalysts for sustainable energy systems.

A mild, configurable, flexible CoNi-LDH(v)/Zn battery based on H-vacancy-induced reversible Zn2+ intercalation

Flexible Zn-based batteries have attracted increasing research interest as essential components of wearable energy storage devices. However, the advancement of flexible aqueous Zn-based batteries based on Co-Ni layered double hydroxide (CoNi-LDH) as the cathode material is hampered by their poor cycling stability and the corrosiveness of alkaline electrolytes. Herein, CoNi-LDH nanosheets enriched with H vacancies (CoNi-LDH(v)) were constructed on a flexible carbon cloth (CC) substrate via electrochemical deposition and activation. The Zn-based battery comprising CoNi-LDH(v)@CC as the cathode exhibited highly reversible conversion reactions and stable operation in 3 M ZnSO4 electrolyte (pH = 4). The battery delivered an excellent specific capacity (225 mA h g−1, 0.26 mA h cm−2), acceptable cycling stability (53.9%, 900 cycles), and high discharging voltage. The abundant H vacancies served as active sites for the reversible intercalation of Zn2+ and the extravasation of NO3− generated channels and space for Zn2+ transport and storage, together enabling an excellent Zn2+ storage capacity. Furthermore, a sandwich-structured solid-state CoNi-LDH(v)@CC//Zn@CC battery was fabricated and was found to exhibit a noteworthy electrochemical performance and mechanical durability. As a proof of concept, the unencapsulated battery powered a digital watch under various deformation conditions and operated stably for 80 h. Additionally, the flexible battery displayed outstanding customizability, maintaining an open-circuit voltage of 1.42 V even after being cut twice. The proposed engineering strategy contributes to the realization of textiles with truly wearable energy-storage devices.

The Positional Effect of an Immobilized Re Tricarbonyl Catalyst for CO2 Reduction.

The storage of renewable energy through the conversion of CO2 to CO provides a viable solution for the intermittent nature of these energy sources. The immobilization of rhenium(I) tricarbonyl molecular complexes is presented through the reductive coupling of bis(diazonium) aryl substituents. The heterogenized complex was characterized through ultra-visible, attenuated total reflectance, infrared reflection absorption spectroscopy, and X-ray photoelectron spectroscopy to probe the electronic structure of the immobilized complex. In addition, studies of cyclic voltammetry, controlled potential electrolysis, and electrochemical impedance spectroscopy were conducted to examine the CO2 reduction activity. The structure and CO2 reduction performance were compared with a previously reported immobilized rhenium(I) tricarbonyl molecular complex to probe the effect of varying the tethering of the aryl substituent from the 5,5'-position to the 4,4'-position of the 2,2'-bipyridine backbone. The immobilized complex on carbon cloth at the 4,4'-position provided excellent selectivity (FECO > 99%) and maximum TONCO and TOFCO values of 3359 and 0.9 s-1, respectively, without the addition of a Bro̷nsted acid source. A nonaqueous flow cell demonstrated the stability of this complex during a 5 h electrolysis. Tethering at the 4,4'-position, compared to the 5,5'-position, yielded lower overall activity for CO2 reduction and was attributed to the difference in growth morphology and formation of aggregations, due to Re-Re dimer formation and π-π stacking interactions within the metallopolymer matrix. For carbon cloth substrates, an optimized catalyst loading was determined to be 44.6 ± 11 nmol/cm2.

One-step hot-press synthesis of amino functionalized Zr-based metal organic framework for determination and speciation of trace inorganic arsenic species in water samples with EDXRF spectrometry

Herein, amino functionalized Zr-based metal organic framework (UiO-66-NH2) on carbon cloth substrate was synthesized by using one-step hot-pressing method and the product (UiO-NH2@CC) was evaluated as a new solid phase extraction (SPE) material for determination and speciation of inorganic arsenic species (As(V) and As(III)) in water samples through energy dispersive X-ray fluorescence (EDXRF) spectrometry. SPE efficiency of UiO-NH2@CC was examined in batch and continuous adsorption (pre-concentration) processes and combination of either batch or continuous pre-concentration process with EDXRF spectrometry proposed analytical method, offering remarkable benefits (i.e., user-friendly, no elution procedure, environmentally friendly and cost-effective, etc.). Batch adsorption studies indicated that As(V) could be selectively adsorbed by UiO-NH2@CC at pH 2 and better represented by Freundlich isotherm model in 60 min of equilibrium time. Continuous adsorption studies at pH 2 demonstrated a drop in As(V) adsorption efficiency of UiO-NH2@CC for sample loading volume above 30 mL with increasing flow rate from 0.3 to 1.0 mL/min and initial As(V) concentration from 20 to 100 µg/L. By considering fortification experiments on real water samples at two levels (5 and 50 µg/L) of As(V) species, both batch and continuous pre-concentration steps coupled with EDXRF spectrometry, with LOD values of 0.790 and 0.220 µg/L, respectively, indicated good recoveries in the range of 87(±11)–104(±7) with no statistically significant differences. Finally, the continuous pre-concentration step followed by EDXRF measurement, as a representative analytical method, was of successful applicability to the speciation of As(III) and As(V) in real water samples with notable advantages (i.e., effortless, economical, practical and reproducible, etc.).

Development of novel plasma process for modification of solid and liquid interfaces for high-energy-density Cu-MnOx supercapacitor electrodes

Supercapacitors are known for their fast-charging capabilities and high-power density, though their energy density is lower compared to common batteries. Modifying the interface of manganese oxide (MnOx) electrodes by incorporating copper (Cu) is a promising method to enhance the energy density of supercapacitors, though it is not yet fully implemented due to the high electrical resistance inherent to MnOx. This work addresses this challenge by incorporating copper oxide into MnOx. A custom-designed atmospheric-pressure plasma device is used to induce super-hydrophilicity in the carbon cloth substrate, thereby improving MnOx electrodeposition. The copper sulfate precursor solution is also treated with direct plasma discharge to increase the copper doping rate in MnOx. The resulting Cu-MnOx supercapacitor electrodes, with copper oxide incorporated into the material, exhibit significantly lower charge transfer resistance and impedance, indicating an improved electrolyte/electrode interface. The assembled asymmetric supercapacitor, featuring Cu-MnOx as the cathode and activated carbon as the anode, demonstrates a specific capacitance of 92.3 F/g at 1 A g-1, a power density of 700 W/kg, and an energy density of 25.13 Wh/kg. This approach is promising for developing next-generation plasma processing technologies and energy storage materials and devices, as well as easy-to-implement surface modifications for improved wettability.

Synergistic heterostructural interface of CoP and WC for high-performance wide pH-universal hydrogen evolution electrocatalysis

The development of cost-effective catalysts with high activity and stability over a wide pH range is urgent, but there are great challenges in the selection and design of catalyst materials. In this work, cobalt phosphide nanoparticles were modified onto tungsten carbide nanowire arrays (CoP@WC/CC) on carbon cloth substrate by a two-step method. The construction of CoP@WC heterostructure results in the downward shift of the d-band center, which optimizes the adsorption energy of catalyst and reaction intermediates. Meanwhile, the synergistic effect of CoP and WC contributes to the alkaline HER kinetic process. In addition, binder-free self-supporting nanoarray have excellent electrical conductivity, large specific surface area and strong structure, which is conducive to charge/matter exchange and catalyst stability. The results show that CoP@WC/CC can effectively drive HER over a wide pH range and exhibit better catalytic performance than the single component control sample. In 0.5 M H2SO4 and 1 M KOH, CoP@WC/CC can drive the current density of 10 mA cm−2 with only 52 and 70 mV, while showing excellent stability without obvious performance degradation during 100 h of constant current test. A proton exchange membrane water electrolysis (PEMWE) using CoP@WC/CC catalyst operates stably for 200,000 s at 30 mA cm−2. This study provides a new reference for the design and development of high efficiency, low cost and wide pH-universal hydrogen evolution electrocatalysts.

Regulation of surface oxygen vacancy of Cu-CeO2/TiO2 heterostructures via fast Joule heating method for enhanced CO2 electrochemical reduction

Strict control of carbon emissions is crucial for expediting the achievement of carbon neutrality. However, the current CO2RR electrocatalytic exhibits numerous shortcomings that impede the enhancement of catalytic activity. Issues such as lengthy catalyst preparation times, and high levels of precious metal content. Additionally, the aggregation of ultrafine nanoparticles contributes to a rapid deterioration in catalytic performance. Herein, a Joule-heating method is efficiently utilized to synthesize heterostructures nano-catalysts for CO2 electroreduction on carbon cloth substrates. This method takes advantage of the thermoelectric coupling of the carbon cloth to achieve carbothermal reduction, while also regulating phase composition and introduction of oxygen vacancies. The Cu-CeO2/TiO2/CC catalyst synthesized in this method showed a current density in CO2 of −32 mA·cm−2 at −1.0 V (vs. RHE). Notably, this catalyst demonstrated high CO selectivity and Faraday efficiency (FECO) of up to 82.5 % at a low potential of −0.3 V (vs. RHE). Optimal electrochemical performance is achieved at a power of 40 W. The ultra-fast temperature change process prevented the agglomeration of catalyst particles and facilitated the construction of a stable heterogeneous interface with a high oxygen vacancy concentration. In conclusion, this study presents a promising approach, particularly for the rapid preparation of low-cost, highly selective non-precious metal electrocatalysts.

Dual-engineering of tungsten doping and carbon incorporation in vanadium carbide arrays to accelerate the polysulfide conversion for lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation electrochemical energy storage systems by virtue of the high energy density, low-cost, and ecofriendliness. Unfortunately, the sluggish sulfur conversion kinetics, notorious shuttle effect of lithium polysulfides (LiPSs) and severe volumetric variation during the lithiation/delithiation process result in insufficient sulfur utilization and fast capacity degradation. Herein, tungsten-doped vanadium carbide nanosheet arrays strongly coupled with a thin nitrogen-doped carbon layer directly grown on carbon cloth substrate (denoted as CC/W-VC@NC) have been conceptually designed as an advanced sulfur host to resolve the aforementioned problems. Specifically, the binder-free CC/W-VC@NC sulfur host not only strongly interacts with LiPSs, but also presents superior electrocatalytic activity for rapid LiPSs conversion. Additionally, the arrayed architecture provides sufficient space for sulfur loading and simultaneously accommodates its volumetric variation. Furthermore, theoretical calculations elucidate that tungsten doping can regulate the electronic structure, improve the electrical conductivity and strengthen the chemisorption toward LiPSs. Attributing to the multifarious advantages, Li-S batteries assembled with CC/W-VC@NC/S cathode exhibit a high initial discharge capacity of 1305.9 mAh/g at 0.1 C, as well as superior rate capability (709.8 mAh/g at 5 C) and good long-term durability (capacity decay rate of only 0.063 % per cycle over 500 cycles at 1 C). This study presents an effective approach to construct transition metal carbides as high-performance sulfur hosts for Li-S batteries.

Synthesis and electrochemical characterizations of RGO-decorated MnO2 nanorods/carbon cloth-based wearable symmetric supercapacitors

The current research explores a facile two-step method for fabricating flexible RGO-decorated MnO2 nanorod electrodes on a carbon cloth substrate, ideal for wearable energy storage devices. The strategy involves first depositing MnO2 nanorods on the carbon cloth utilizing a hydrothermal technique, followed by a simple ex-situ decoration with reduced graphene oxide by varying concentrations. Through comprehensive physical and electrochemical analyses, the impact of different concentrations of graphene oxide on the physical and electrochemical characteristics of MnO2 electrodes is thoroughly examined. Among the investigated concentrations of graphene oxide, the RGO-decorated MnO2 electrode featuring a 20 mg/100ml concentration of graphene oxide showcased the maximum specific capacitance reaching 1072.28 F/g at a 5 mV/sec in a 1M Na2SO4 electrolyte. Furthermore, this electrode demonstrated commendable long-term cycle stability, preserving over 87% of its original capacitance after enduring 2000 cycles of charge and discharge. A symmetric prototype supercapacitor device has been constructed to assess their practical utility utilizing symmetric electrodes and an aqueous electrolyte. This symmetric device exhibits promising electrochemical properties, underscoring the potential of the developed electrodes for real-world implementation. The remarkable structural, morphological, and electrochemical characteristic attributes of RGO-decorated MnO2 nanorods grown on the carbon cloth substrate position them as superior electrode materials tailored for the burgeoning realm of wearable energy storage devices, paving the way for advanced flexible and efficient energy storage solutions.

Graphitic carbon nitride functionalized with NiO nanoaggregates: An X-ray photoelectron spectroscopy investigation

The design and synthesis of low-cost oxygen evolution reaction (OER) photoelectrocatalysts endowed with high activity and durability is of utmost importance for sustainable energy generation via solar-assisted water splitting. In this regard, and in the framework of our recent activities, we have focused on the electrophoretic deposition of graphitic carbon nitride (gCN) specimens containing dispersed NiO nanoaggregates on carbon cloth substrates. In the present study, the attention is devoted to the x-ray photoelectron spectroscopy characterization of a representative gCN–NiO specimen. In particular, we provide an analysis of C 1s, N 1s, O 1s, and Ni 2p regions, discussing in detail the main spectral features. The obtained results, that provide evidence for a direct electronic interplay between the single material components, may serve as a useful comparison for additional research on analogous materials for energy and environmental applications.

(Invited) Structural Lithium-Ion Battery Based on LiFePO4/Reduced Graphene Oxide Composite Cathode and Graphene Anode Prepared via Electrophoretic Deposition on Carbon Cloth

Structural lithium-ion batteries based on binder-free LiFePO4/reduced graphene oxide composite cathode electrode and graphene anode electrode are prepared respectively via electrophoretic co-deposition of LiFePO4, reduced graphene oxide, and carbon black on carbon cloth substrate for the cathode, and graphene oxide and carbon black on carbon cloth substrate for the anode. Following deposition, the electrode materials were dried. The graphene oxide of the anode was reduced to graphene via rapid thermal annealing. Possessing excellent stiffness, strength-to-weight ratio, and good electrical conductivity, the carbon cloth substrate serves multifunctional roles in the battery: as structural reinforcement and mechanical load bearing element and as current collector. Given its good electrical conductivity, high aspect ratio, and high surface area, reduced graphene oxide improves electrical conductivity within the cathode and provides sites for hosting LiFePO4; this enhances reversible Li ion extraction from the host during cycling. Graphene with its good electrical conductivity and high aspect ratio provides sites for insertion of Li ions in the anode; this enhances the aerial lithiation capacity of the battery system. Carbon black enhances conductivity within the two electrodes and reduces interfacial impedance. The electrochemical properties of the electrodes are strongly correlated to their microstructure and phase composition. Electrochemical characterization of the electrodes and their performance in half-cell and full cell configurations are evaluated. Additionally, Li-ion diffusivity within the materials is evaluated with three independent electroanalytical methods, including potentiostatic and galvanostatic and intermittent titration techniques, and electrochemical impedance spectroscopy.

Electrochemical Analysis Comparison of Nitrogen Undoped and Doped Ti3C2Tx/Co3O4 Hybrid Composites on Carbon Cloth for Application as Electrode in Supercapacitor

Supercapacitor provides great potential for good energy storage devices application, compared with other energy storage such as rechargeable batteries, fuel cell, dielectric capacitors and so on. Freestanding and flexible electrodes are vital for the development of flexible and wearable devices that store energy. But the significant trade-off between mechanical flexibility and electrode electrochemical performance limits the fabrication of efficient energy storage systems. In this research, we report the synthesis of a 2D material Ti3C2Tx and Co NPs on carbon cloth (CC) substrate. Co NPs was synthesized by microplasma reactors which eliminate harmful reducing agents and are efficient and cost-effective. And the Co NPs/Ti3C2Tx were synthesized by hydrothermal method for supercapacitor. These materials were characterized by scanning electron microscopy (SEM) Energy Dispersive Spectroscopy and X-Ray Diffraction for morphology and phases analysis. Besides these Transmission electron microscopies (TEM) and X-ray Photoelectron spectroscopy (XPS) were also done. For electrochemical analysis these materials were applied on the 2.25 cm2 carbon cloth as active material (working electrode) by various electrochemical techniques in 1 M H2SO4 electrolyte. The Co NPs/Ti3C2Tx electrode had a maximum gravimetric capacity of 52 mAh g-1, specific capacitance of 580 mF cm-2 and 240 F g-1 at the current density of 1 mA cm-2. Figure 1

Engineering Water-Lotus-like Iridium-Cobalt Carbonate Hydroxides on Plasma-Treated Carbon Fibers for Enhanced Electrocatalytic Oxygen Evolution.

The sluggish kinetics of the oxygen evolution reaction (OER) in alkaline water electrolysis remains a significant challenge for developing high-efficiency electrocatalytic systems. In this study, we present a three-dimensional, micrometer-sized iridium oxide (IrO2)-decorated cobalt carbonate hydroxide (IrO2-P-CoCH) electrocatalyst, which is engineered in situ on a carbon cloth (CC) substrate pretreated with atmospheric-pressure dielectric barrier discharge (DBD) plasma (PCC). The electrocatalyst features petal-like structures composed of nanosized rods, providing abundant reactive areas and sites, including the oxygen vacancy caused by the air-DBD plasma. As a result, the IrO2-P-CoCH/PCC electrocatalyst demonstrates an outstanding OER performance, with overpotentials of only 190 and 300 mV required to achieve current densities of 10 mA cm-2 (j10) and 300 mA cm-2 (j300), respectively, along with a low Tafel slope of 48.1 mV dec-1 in 1.0 M KOH. Remarkably, benefiting from rich active sites exposed on the IrO2-P-CoCH (Ir) heterostructure, the synergistic effect between IrO2 and CoCH enhances the charge delivery rates, and the IrO2-P-CoCH/PCC exhibits a superior electrocatalytic activity at a high current density (300 mV/j300) compared to the commercial benchmarked RuO2/PCC (470 mV/j300). Furthermore, the IrO2-P-CoCH/PCC electrocatalyst shows exceptional OER stability, with a mere 1.3% decrease with a current density of j10 for 100 h testing, surpassing most OER catalysts based on CC substrates. This work introduces a novel approach for designing high-performance OER electrocatalysts on flexible electrode substrates.

Investigation of polyaniline electrodeposition on hydrophilic/hydrophobic carbon cloth substrates for symmetric coin cell supercapacitors

Investigation of polyaniline electrodeposition on hydrophilic/hydrophobic carbon cloth substrates for symmetric coin cell supercapacitors