Bare Carbon Cloth Research Articles

Activated carbon derived from ground nutshell as a metal-free oxygen reduction catalyst for air cathode in single chamber microbial fuel cell

A single-chamber microbial fuel cell (SCMFC) was constructed using activated carbon derived from ground nutshells (GAC) as a metal-free cathode catalyst. The prepared cathode catalyst was characterized by X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and Field emission scanning electron microscopy (FE-SEM), which demonstrates the chemical composition and the surface morphology of the synthesized material. The electrochemical characteristics of the cathode were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) analysis, which confirmed the high charge transfer capacity and catalytic activity property of GAC catalyst material. The MFC with GAC catalyst produces a maximum output voltage of 0.619 V and which is 1.61 times greater than that of bare carbon cloth (CC). For Pt/C and GAC-modified CC, high power density values of 0.763 W m−2 and 0.521 W m−2 were obtained at current densities 1.65 A m−2 and 1.0 A m−2, respectively at 100 Ω. These results demonstrate that the GAC/CC is a promising cost-effective cathode catalyst for SCMFC.

Electrochemical performance of aqueous asymmetric supercapacitor based on synthesized tin oxide positive and commercial titanium dioxide negative electrodes

An effective strategy for the fabrication of aqueous asymmetric supercapacitor (AASC) with an ultra-high mass loading of electroactive materials (~38.3 mg cm−2) is reported in the present work. The electrodeposited ruthenium oxide on bare carbon cloth (RuO2@BCC) serves as a flexible, lightweight and conductive current collector for the AASC. The synthesized tin oxide (S-SnO2NPs) and commercially available titanium dioxide (C-TiO2NPs) nanoparticles were spin-coated on RuO2@BCC current collector and utilized as positive and negative electrodes for the fabrication of AASC respectively. The electrochemical measurement showed that the AASC delivered maximum areal capacitance of 58 mF cm−2 at a scan rate of 1 mA cm−2 and capacitance retention rate of 86.5% after 10,000 charge-discharge cycles within working voltage of 1.2 V for the total areal mass loading up to ~38.3 mg cm−2 of electroactive materials. This work provides a new approach to built AASC with an ultra-high areal mass loading of electroactive materials with good electrochemical properties, demonstrating its promising practical application for energy storage devices.

A Carbon-Cloth Anode Electroplated with Iron Nanostructure for Microbial Fuel Cell Operated with Real Wastewater

Microbial fuel cell (MFC) is an emerging method for extracting energy from wastewater. The power generated from such systems is low due to the sluggish electron transfer from the inside of the biocatalyst to the anode surface. One strategy for enhancing the electron transfer rate is anode modification. In this study, iron nanostructure was synthesized on a carbon cloth (CC) via a simple electroplating technique, and later investigated as a bio-anode in an MFC operated with real wastewater. The performance of an MFC with a nano-layer of iron was compared to that using bare CC. The results demonstrated that the open-circuit voltage increased from 600 mV in the case of bare CC to 800 mV in the case of the iron modified CC, showing a 33% increase in OCV. This increase in OCV can be credited to the decrease in the anode potential from 0.16 V vs. Ag/AgCl in the case of bare CC, to −0.01 V vs. Ag/AgCl in the case of the modified CC. The power output in the case of the modified electrode was 80 mW/m2—two times that of the MFC using the bare CC. Furthermore, the steady-state current in the case of the iron modified carbon cloth was two times that of the bare CC electrode. The improved performance was correlated to the enhanced electron transfer between the microorganisms and the iron-plated surface, along with the increase of the anode surface- as confirmed from the electrochemical impedance spectroscopy and the surface morphology, respectively.

High mass loading tin oxide-ruthenium oxide-based nanocomposite electrode for supercapacitor application

Abstract The electrochemical performance of tin oxide-ruthenium oxide-based (S-SnO2NPs-RuO2@BCC) nanocomposite electrode fabricated using electrodeposition of ruthenium oxide (RuO2) followed by spin coating of synthesized tin oxide nanoparticles (S-SnO2NPs) on bare carbon cloth (BCC) current collector was studied. The prepared electrodes were characterized by field emission gun scanning electron microscopy, energy dispersive spectroscopy, and x-ray photoelectron spectroscopy. The results confirmed the presence of wire-shaped RuO2 and nanosphere S-SnO2 morphology on the BCC surface. The electrochemical measurement showed that the S-SnO2NPs-RuO2@BCC electrode exhibited comparatively higher areal capacitance (794 mF cm−2) than that of the RuO2@BCC electrode (464 mF cm−2) at a scan rate of 5 mVs−1 in 1 M H2SO4. Trasatti's analysis also showed that the loading of S-SnO2NPs on the RuO2@BCC electrode enhanced the capacitive capacitance nearly three times to that of the RuO2@BCC electrode. Furthermore, symmetrical supercapacitor (SS) was fabricated using S-SnO2NPs-RuO2@BCC electrodes with the total mass loading ~ 20 ± 0.2 mg cm−2 of S-SnO2NPs. SS displayed maximum areal capacitance of 184 mF cm−2 at a scan rate of 5 mVs−1 and a capacitance retention rate of 87.5 % after 5000 charge-discharge cycles at a current density of 10 mA cm−2 in PVA-H2SO4.

Enhancement of electrochemical properties of hydrous ruthenium oxide nanoparticles coated on chemically activated carbon cloth for solid-state symmetrical supercapacitor application

Electrochemical performance of bare carbon cloth (BCC) and chemically activated carbon cloth (CACC) as current collectors were studied for supercapacitor applications. The prepared hydrous ruthenium oxide nanoparticles (H–RuO2NPs) using gallic acid monohydrate coated on both BCC and CACC and employed as pseudocapacitive electrodes in aqueous neutral (1 M Na2SO4) electrolyte. The specific capacitance obtained for H–RuO2NPs coated on CACC (H–RuO2NPs@CACC) using constant current charge-discharge measurements was 837 F g−1 at a current density of 2 A g−1 which was 3.87 times higher than the H–RuO2NPs coated on BCC (H–RuO2NPs@BCC). Moreover, the capacitance retention rate for H–RuO2NPs@CACC and H–RuO2NPs@BCC was 97.54% and 95.8% after 5000 cycles at 20 Ag-1 respectively. Furthermore, the symmetrical supercapacitor (SS) fabricated using H–RuO2NPs@CACC electrodes delivers the capacitance up to 796 Fg- 1 at 2 mVs−1 with capacitance retention of 91.8% after 5000 cycles at 10 Ag-1 for total mass loading of 10 mg cm−2 in hydrogel polymer electrolyte (PVA- Na2SO4). The energy density of SS was 156 Wh kg−1 at a current density of 5 A g−1. The obtained results of SS suggest that the H–RuO2NPs@CACC electrode can be utilized for a high-performance energy storage device.

Enhanced Cr reduction and bioelectricity production in microbial fuel cells using polypyrrole-coated MnO2 on carbon cloth

Hexavalent chromium (Cr(VI)) is a carcinogenic pollutant that can be transformed into less toxic trivalent chromium (III). Microbial fuel cells can be used simultaneously to reduce wastewater Cr(VI) and to generate bioelectricity, yet actual cell cathodes are not well-optimized for high performance. Here, we tested the reduction of Cr(VI) using an abiotic cathode made of carbon cloth coated by polypyrrole-coated turf-like manganese dioxide in a two-chamber cell. Results show a 100% Cr(VI) removal within 32 h using an initial catholyte at pH 2 and 50 mg L−1 Cr(VI). The reduction rate of 1.56 mg L−3 h−1 is 175% higher than for the bare carbon cloth cathode, of 0.89 mg L−3 h−1. The maximum power density of 1429 mW m−2 was higher than that for the polypyrrole cathode, of 1017 ± 65 mW m−2, the MnO2 cathode, of 648 mW m−2, and the carbon cloth cathode, of 595 mW m−2. Noteworthy, Cr reduction was efficient without the use of electron transfer mediators such as anthraquinone-2,6-disulfonate. Moreover, polypyrrole allowed an excellent stability of the electrode under acidic conditions.

ZIF-8/PEDOT @ flexible carbon cloth electrode as highly efficient electrocatalyst for oxygen reduction reaction

Design and fabrication of highly efficient and low-cost oxygen reduction reaction (ORR) electrocatalysts is of paramount importance for practical applications. Herein, we proposed a cost-effective, metal-free catalyst based on ZIF-8 metal-organic framework nanoparticles/electro-polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) film on the surface of flexible carbon cloth (CC) electrode (ZIF-8/PEDOT/CC) via a two-step procedure. For this purpose, worm-like PEDOT nanostructures were deposited on the surface of carbon fibers using a pulse electro-polymerization technique followed by facile growth of ZIF-8 polyhedra nanoparticles via a chemical bath deposition method. The ORR measurements in O2-saturated KOH electrolyte solution using the modified CC electrode demonstrated that the prepared electrode exhibits remarkable electrocatalytic activity towards ORR with 8 times increase in the cathodic current density compared to bare CC (J = 0.13–1.1 mA/cm2) along with lower overpotential due to the synergetic effects between ZIF-8 nanoparticles as particularly porous nanostructure act as electrolyte reservoirs and highly conductive PEDOT film. The Kouteckey-Levich analysis for the ZIF-8/PEDOT-modified CC electrode revealed that the oxygen reduction reaction proceeds via a nearly four-electron pathway along with superior tolerance to methanol crossover as well as enhanced stability in alkaline solution compared to the gold standard commercial Pt catalyst.

High‐Performance Flexible Asymmetric Supercapacitors Facilitated by N‐doped Porous Vertical Graphene Nanomesh Arrays

AbstractThe design of self‐supporting electrode scaffold with large surface area, good flexibility, and high electrical conductivity is of great significance to the development of high performance flexible supercapacitors. Herein, we report the fabrication of N‐doped porous vertical graphene nanomesh arrays (NVGMs) on flexible carbon cloth (CC) substrate (CC@NVGMs) via a facile self‐sacrificing template method. The NVGMs provide large surface area, more growth sites of active materials, good electrical conductivity and short diffusion paths, leading to greatly enhanced performance. After decorating MnO2 nanosheets and polypyrrole films on the NVGMs, the hierarchical nanohybrid electrodes show notable improvement of areal capacitances, greatly decrease of equivalent series resistance, significantly enhancement of rate performance, compare to those of the active materials on bare CC. Furthermore, the flexible asymmetric supercapacitor is assembled by these two nanohybrid electrodes has an energy density of up to 1.92 mWh cm−3.

Facile fabrication of Au@polyaniline core-shell nanocomposite as efficient anodic catalyst for microbial fuel cells

Electrode modification with different catalytic nanoparticles or nanocomposites was promising for improving the performance of microbial fuel cells (MFCs). However, direct modification of electrode with metal nanoparticles encountered the drawback of low biocompability although these nanoparticles showed intriguing catalytic properties. In this work, conductive polymer encapsulation of metal nanoparticles was developed to improve the biocompability and then applied for anode modification in MFCs. The Au@polyaniline (Au@PANI) core-shell nanocomposite was simply synthesized with an aid of ionic liquid. Morphological, crystalline and structural properties were studied in details with SEM, TEM, XRD and FTIR analyses and an intact PANI shell covered on the sphere of Au nanoparticle was observed. Upon modification of this core-shell nanocomposite on carbon cloth electrode, significant improvement on bioelectrochemical activity was observed when compared with bare carbon cloth or carbon cloth modified with naked Au nanoparticles. As a result, the performance of MFCs was enhanced from 332 mW/m2 to 804 ± 73 mW/m2 by Au@PANI modification. These results demonstrated that encapsulation of metal nanoparticle with biocompatible and conductive polymer is promising for bioelectrochemical applications.

Cauliflower‐like polypyrrole@MnO2 modified carbon cloth as a capacitive anode for high‐performance microbial fuel cells

AbstractBACKGROUNDThe morphology and size of MnO2 that deposited on a carbon clothelectrode have dramatic effects on the electrochemical properties and cycling life. Currently, MnO2 and its composite structures with zero‐dimensional (0D) nanospheres, one‐dimension (1D) nanotubes and two‐dimension (2D) nanomesh have been successfully synthesized and employed in MFC. Hence, the development of a three‐dimensional (3D) flexible, cost‐effective and high‐performance anode is of great significance for microbial energy harvesting.RESULTHerein, we have fabricated 3D cauliflower‐like polypyrrole@manganese dioxide (PPy@MnO2) composites, which are successfully grown on carbon cloth (CC) anode by electrodeposition to promote the power production and storage in microbial fuel cells (MFCs). Impressively, the as‐prepared PPy@MnO2 modified CC anode delivers a power density of 2139.7 ± 17.5 mW m−2 and produces an areal capacitance of 1120 ± 12.8 mF cm−2, which is 3.58 and 4.84 folds higher than that with bare CC anode, benefiting from the unique cauliflower‐like 3D architecture with increased active centers that host the bacteria for more efficient charge transfer. Electrochemical analyses indicate that the PPy@MnO2 modified CC electrode has excellent electrochemical activity, capacitive behavior and long‐term cyclabilities with smooth surface morphology and high porosity.CONCLUSIONThese findings not only provide a facile electrodeposition strategy for PPy@MnO2 nanoflowers modified CC anode, but also demonstrates its potential for the production and storage of energy simultaneously in MFC application. © 2019 Society of Chemical Industry

Bioelectricity Generation by Corynebacterium glutamicum with Redox-Hydrogel-Modified Carbon Electrode

This work studied Gram-positive and weak electricigen Corynebacterium glutamicum for its ability to transfer electrons and to produce bioelectricity in microbial fuel cells (MFCs). The electrochemical and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) results revealed that C. glutamicum had the potential to mediate electron transfer to an electrode by emitting its own extracellular electron shuttles such as flavins. To enhance the current collection from C. glutamicum, a carbon cloth anode was modified with ferrocene-branched chitosan hydrogel (redox-hydrogel). The maximum current density of the ferrocene-branched chitosan redox hydrogel anode with C. glutamicum was drastically increased to 120 µA cm−2 relative to a bare carbon cloth electrode with C. glutamicum (261 nA cm−2). The power density and polarization curves for the MFC operation with the redox-hydrogel-modified anode showed that C. glutamicum effectively generated bioelectricity by means of the redox-hydrogel anode. The results suggest that, in such an electro-fermentation process, ferrocene-branched chitosan hydrogel grafted onto an anode surface would also facilitate both electron transfer from C. glutamicum to the anode and bioelectricity generation.

Enhanced current production of the anode modified by microalgae derived nitrogen-rich biocarbon for microbial fuel cells

In this study, nitrogen-rich biocarbon derived from carbonized Chlorella pyrenoidosa (CCP) was proposed to enhance the current generation from the anode of microbial fuel cells (MFCs). The results revealed that the carbon cloth decorated by CCP (CCP-CC) achieved the highest bioelectrocatalytic current density of 13.44 ± 0.34 A m−2 after the successful startup, which was 12% and 22% higher than those with carbon black (CB-CC) and the bare carbon cloth (CC), respectively. The results can be attributed to the advantages of CCP-CC over CB-CC and CC in terms of a higher active biomass content, a much smaller charge transfer resistance resulting from the facilitated direct electron transfer due to the presence of N-containing functional groups in CCP and the enhanced mediated electron transfer caused by the larger surface area of the CCP-CC anode for the flavin mediator adsorption.

Two dimensional α-MoO3 nanosheets decorated carbon cloth electrodes for high-performance supercapacitors

The production of two dimensional (2D) layers, especially nanosheet is of significant importance to develop supercapacitors. Herein, reactive radio-frequency magnetron sputtering method is employed to the 2D α-MoO3 nanosheet preparations on carbon cloth substrate. As-prepared 2D α-MoO3 nanosheet coated carbon cloth has been characterized by XRD, UV–vis, Raman, FE-SEM, EDX techniques. Supercapacitor performance of 2D α-MoO3 nanosheet coated carbon cloth is tested from cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) techniques in 1.0 M aqueous Na2SO4 electrolyte. 2D α-MoO3 nanosheet coated carbon cloth delivers the specific capacitance 240 F g−1 at current density of 1.5 mA cm−2 with capacity retention of 78.8% for 5000 cycles at 2.5 mA cm−2. Compared to bare carbon cloth and α-MoO3 decorated carbon cloth at room temperature, 2D α-MoO3 nanosheet coated carbon cloth exhibits much higher specific capacity, superior cyclability, and good rate capability, highlighting the advantages of hierarchical nanosheet and high surface area in the MoO3 structure.

High-performance 2.5 V flexible aqueous asymmetric supercapacitors based on K+/Na+-inserted MnO2 nanosheets

The voltage of aqueous asymmetric supercapacitors is usually limited within 2 V, which hampers their practical application as energy storage device. Herein, three-dimensional porous alkaline ions-inserted δ-MnO2 nanosheet arrays are prepared via hydrothermal synthesis on a modified carbon cloth substrate with N-doped carbon nanowire network (N-CNN). Interestingly enough, the potential window of the MnO2 nanosheet arrays can be extended to 1.2 V versus saturated calomel electrode (vs. SCE). The charge storage mechanism of δ-MnO2 for serving as the cathode is discussed which reveals the behavior of insertion/extraction for alkaline ions in electrolyte solution. Carbon-coated Fe2O3 nanorod arrays supported on bare carbon cloth are also fabricated successfully, which can stably function as the anode in a broad negative potential window of −1.3-0 V (vs. SCE). Consequently, a flexible aqueous asymmetric supercapacitor with a high voltage of 2.5 V is constructed by using MnO2@N-CNN as the cathode and C@Fe2O3 as the anode. The MnO2@N-CNN//C@Fe2O3 device displays a large energy density up to 1.43 mWh/cm3 as well as excellent rate capability and cycling performance, which is among the best supercapacitors based on MnO2 materials. This work paves a novel way to develop high-voltage aqueous asymmetric energy storage devices with large capacitance and energy density.

High-Coulombic-Efficiency Carbon/Li Clusters Composite Anode without Precycling or Prelithiation.

Lithium metal has attracted much research interest as a possible anode material for high-energy-density lithium-ion batteries in recent years. However, its practical use is severely limited by uncontrollable deposition, volume expansion, and dendrite formation. Here, a metastable state of Li, Li cluster, that forms between LiC6 and Li dendrites when over-lithiating carbon cloth (CC) is discovered. The Li clusters with sizes in the micrometer and submicrometer scale own outstanding electrochemical reversibility between Li+ and Li, allowing the CC/Li clusters composite anode to demonstrate a high first-cycle coulombic efficiency (CE) of 94.5% ± 1.0% and a stable CE of 99.9% for 160 cycles, which is exceptional for a carbon/lithium composite anode. The CC/Li clusters composite anode shows a high capacity of 3 mAh cm-2 contributed by both Li+ intercalation and Li-cluster formation, and excellent cycling stability with a signature sloping voltage profile. Furthermore, the CC/Li clusters composite anode can be assembled into full cells without precycling or prelithiation. The full cells containing bare CC as the anode and excessive LiCoO2 as the cathode exhibit high specific capacity and good cyclic stability in 200 cycles, stressing the advantage of controlled formation of Li clusters.

Carbon Nanotubes Modified Carbon Cloth Cathode Electrode for Self-Pumping Enzymatic Biofuel Cell

A self-pumping enzymatic biofuel cell (self-pumping EBC) with a new cathodic catalyst which was modified by coating the mixture of carbon nanotubes/caffeic acid (CNTs/CA) on a carbon cloth (CC) to form a CNTs/CA/CC cathode electrode was fabricated. By using UV spectrophotometer, the absorbance of CA, CNTs, and the CNTs/CA composite was observed. To evaluate how the CNTs/CA/CC cathodic electrode improves the electrochemical performance of the self-pumping EBC, the measurement of the redox reaction current peak by cyclic voltammetry (CV) was implemented. In accordance with CV measurement, the utilization of the modified CNTs/CA/CC cathodic electrode exhibited a higher oxygen reduction current peak at 319.1μA under the saturated oxygen. The anode and cathode flow rates were 0.416μls−1and 0.844μls−1which contribute to obtaining the capillary driven liquid efficiency as 30% for the former and 59% for the latter. Moreover, the self-pumping EBC performance tests showed that the maximum power density (MPD) of the self-pumping EBC with the modified cathodic electrode achieved 0.592 mWcm−2which improved 10% in the performance compared with the bare CC electrode, 0.534 mWcm−2.

Morphology Tailored Cobalt Oxide Nanoarchitectures Over Flexible Platform For Hazardous Organic Dye Degradation Under Visible Light

Morphology tuned cobalt oxide (Co3O4) nanoarchitectures were realized on foldable substrate by a very facile approach. Starting with bare carbon cloth, firstly cobalt oxide seed layer was prepared on it following which it treated hydrothermally for the synthesis of nanoform with different shape namely nanorod and nanosheet. Morphological features of the samples were examined by FESEM analysis. To attain the clear insight of its elemental composition EDX analysis and elemental mapping of both samples were carried out. Finally as an immediate usability of the shape controlled nanostructure we have examined their photocatalytic performance under visible light exposure taking rhodamine B dye as model contaminant.

Surface Modified Carbon Cloth via Nitrogen Plasma for Supercapacitor Applications

Carbon cloth (CC) is a basic component for various electrochemical applications including supercapacitors, batteries, and catalysts. However, the hydrophobic nature and poor compatibility of CC with electrolyte ions remain an issue. In the present work, we developed a simple yet effective nitrogen plasma approach to induce nanostructuring over the CC, thereby significantly increasing the wettability and surface area of the CC, which both favor robust electrochemical reactions. In addition to this, nitrogen doping on the surface of the CC allowed more electroactive species for electrochemical reactions. Benefiting from these integrated merits, the plasma-treated nitrogen-doped CC (NCC) shows excellent supercapacitive features including an areal capacitance of 741 mF/cm2, which is much higher than that of the bare CC. Moreover, the NCC shows excellent cycling stability over 5000 charge–discharge cycles without losing its initial capacitance. The presented approach provides an innovative route to design and develop highly efficient carbon-based electrodes for supercapacitor applications.

2D Metal-Organic Frameworks Derived Nanocarbon Arrays for Substrate Enhancement in Flexible Supercapacitors.

Direct assembling of active materials on carbon cloth (CC) is a promising way to achieve flexible electrodes for energy storage. However, the overall surface area and electrical conductivity of such electrodes are usually limited. Herein, 2D metal-organic framework derived nanocarbon nanowall (MOFC) arrays are successfully developed on carbon cloth by a facile solution + carbonization process. Upon growth of the MOFC arrays, the sites for growth of the active materials are greatly increased, and the equivalent series resistance is decreased, which contribute to the enhancement of the bare CC substrate. After decorating ultrathin flakes of MnO2 and Bi2 O3 on the flexible CC/MOFC substrate, the hierarchical electrode materials show an abrupt improvement of areal capacitances by around 50% and 100%, respectively, compared to those of the active materials on pristine carbon cloth. A flexible supercapacitor can be further assembled using two hierarchical electrodes, which demonstrates an energy density of 124.8 µWh cm-2 at the power density of 2.55 mW cm-2 .

Different modified multi-walled carbon nanotube–based anodes to improve the performance of microbial fuel cells

To clearly illustrate the activity effect of multi-walled carbon nanotubes (MWCNTs) and their functionality on anodic exoelectrogen in microbial fuel cells (MFCs), the growth of E. coli and anode biofilm on MWCNT-, MWCNTCOOH and MWCNTNH2 modified anodes were compared with a bare carbon cloth anode. The activity effect was characterized by the amount of colony-forming units (CFUs), activity biomass, morphology of biofilms and cyclic voltammetric (CV). The results showed that MWCNTs, MWCNT-COOH and MWCNT-NH2 exhibited good biocompatibility on exoelectrogenic bacteria. The performance of MFCs were improved through the introduction of MWCNT-modified anodes, especially in the presence of COOH/NH2 groups. The MFCs with the MWCNTCOOHmodified anode achieved a maximum power density of 560.40 mW/m2, which was 49% higher than that obtained with pure carbon cloth. In conclusion, the positive effects of MWCNTs and their functionality were evaluated for promoting biofilm formation, biodegradation and electron transfer on anodes. Specifically, the MWCNTCOOHmodified anode demonstrated the largest application potential for the development of MFCs.