Capacitive properties of polypyrrole/activated carbon composite

Electrochemical synthesis of polypyrrole (PPy) and polypyrrole / activated carbon (PPy / AC) - composite films, with a thickness between 0.5 and 15 ?m were performed in a three electrode cell containing 0.1 mol dm-3 Py, 0.5 mol dm-3 NaClO4 dissolved in ACN, and dispersed particles of AC (30 g dm-3). Electrochemical characterization of PPy and PPy / AC composites was performed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. The linear dependences of the capacitance (qC), redox capacitance (qred), and limiting capacitance (CL) of PPy and PPy / AC - composite films on their thickness (L), obtained by electrochemical and impedance analysis, indicate a nearly homogeneous distribution of the incorporated AC particles in the composite films (correlation coefficient between 0.991 and 0.998). The significant enhancement of qC, qred, and CL, was observed for composite films (for ?40 ? 5%) in respect to that of the ?pure? PPy. The decreased values of a volume resistivity in the reduced state of the composite film, ? = 1.3 ? 106 ? cm (for L = 7.5 ?m), for two orders of magnitude, compared to that of PPy - film with the same thickness, ? ? 108 ? cm, was also noticed.

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Physical Properties of Starch/Powdered Activated Carbon Composite Films

Polymers ◽

10.3390/polym13244406 ◽

2021 ◽

Vol 13 (24) ◽

pp. 4406

Author(s):

Anita Kwaśniewska ◽

Michał Świetlicki ◽

Adam Prószyński ◽

Grzegorz Gładyszewski

Keyword(s):

Mechanical Properties ◽

Activated Carbon ◽

Water Vapor ◽

Water Solubility ◽

Composite Films ◽

Water Vapor Permeability ◽

Barrier Properties ◽

Carbon Composite ◽

Powdered Activated Carbon ◽

Vapor Permeability

In the present study, starch/powdered activated carbon composite films were prepared by incorporating various amounts of powdered activated carbon (PAC)—1–5, 10, and 15 %—into a starch matrix, using the solvent casting method. The effect of PAC addition on the biopolymer film was investigated. The mechanical properties were examined by ultra-nanoindentation, nanoscratch, and micro-tensile tests. Since the mechanical properties of biopolymer films are correlated with their structure, the effect of PAC addition was tested using X-ray diffraction. The surface parameters morphology and wettability were analyzed by atomic force microscopy (AFM) and contact angle measurements. The barrier properties were examined by determining water vapor permeability and the water solubility index. The obtained results did not show a monotonic dependence of the mechanical parameters on PAC content, with the exception of the maximum strain, which decreased as the amount of the additive increased. The visible effect of PAC addition was manifested in changes in the adhesive force value and in water vapor permeability (WVP). The barrier properties decreased with the increase of the filler content.

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Substitution of Acetylene Black by Using Modified Flake Graphite Applied in Activated Carbon Supercapacitors

MATEC Web of Conferences ◽

10.1051/matecconf/201816003005 ◽

2018 ◽

Vol 160 ◽

pp. 03005

Author(s):

Peng Zhao ◽

Chunmei He ◽

Wencheng Hu

Keyword(s):

Electron Microscopy ◽

Activated Carbon ◽

Electrochemical Impedance ◽

Normal Pressure ◽

Acetylene Black ◽

Flake Graphite ◽

X Ray Diffraction ◽

Transmission Electron ◽

Capacitive Properties ◽

Methyl Pyrrolidone

Flake graphite was mechanically modified at different times in N-methyl pyrrolidone under normal pressure. The results of the scanning electron microscopy, X-ray diffraction, and transmission electron microscopy suggested that the structure of the flake graphite was modified. The crystallinity of the flake graphite, and many defects were introduced into the material. The evaluation of capacitor performance by cyclic voltammetry, galvanostatic charge/discharge tests, and electrochemical impedance spectroscopy was also performed. Results showed that the electrochemical performance of flake graphite was strongly enhanced, particularly when it was exfoliated for 6 h. Moreover, the electrochemical capacitive properties of activated carbon were obviously enhanced through the substitution of acetylene black by flake graphite modified for 6 h.

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Adsorption of neutral red dye by chitosan and activated carbon composite films

Heliyon ◽

10.1016/j.heliyon.2021.e07629 ◽

2021 ◽

pp. e07629

Author(s):

Fabiana Paiva de Freitas ◽

Ana Márcia M.L. Carvalho ◽

Angélica de Cássia Carneiro Oliveira ◽

Mateus Alves de Magalhães ◽

Mariana Fonseca Xisto ◽

...

Keyword(s):

Activated Carbon ◽

Composite Films ◽

Carbon Composite ◽

Neutral Red ◽

Red Dye

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Capacitive properties of low potential electro-polymerized polyfluorene and activated carbon composite electrode

Science China Chemistry ◽

10.1007/s11426-011-4387-7 ◽

2011 ◽

Vol 55 (3) ◽

pp. 352-358 ◽

Cited By ~ 2

Author(s):

Wei Liu ◽

MingLiang Sun ◽

Wei Wang ◽

LingXia Song ◽

HongLun Ge ◽

...

Keyword(s):

Activated Carbon ◽

Composite Electrode ◽

Carbon Composite ◽

Capacitive Properties ◽

Carbon Composite Electrode

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Transport of Protons and Capacitive Properties of the Nylon/Porphyrin/Graphene Oxide Coating

10.20944/preprints201709.0015.v1 ◽

2017 ◽

Author(s):

César A. García-Pérez ◽

Carmina Menchaca-Campos ◽

Miguel A. García-Sánchez ◽

Ociel Rodríguez-Pérez ◽

Jorge Uruchurtu

Keyword(s):

Graphene Oxide ◽

Electrochemical Impedance ◽

Composite Films ◽

Oxide Coating ◽

Film Coating ◽

Bipolar Plates ◽

Transfer Product ◽

Low Frequencies ◽

Capacitive Properties ◽

Acid Environment

Electrochemical impedance (EI) measurements were performed to evaluate the nylon 66/-tetra-(para-aminophenyl) porphyrin (H2T(p-NH2)PP)/graphene oxide (GO) film coating on stainless steel and compared to the nylon/H2T(p-NH2)PP and nylon/GO film samples using 1M H2SO4 as electrolyte. The nylon/H2T(p-NH2)PP and nylon/GO composite films showed high electrochemical impedance in the order of 109 ohm-cm2 and a system controlled by mass transfer, product of a diffusion process at low frequencies with a resistance up to 5 orders of magnitude, indicating the diffusion of protons through the coating and a decrease in the metal dissolution. Otherwise, the nylon/H2T(p-NH2)PP/GO film compound evaluated show good ionic conductivity and electrochemical stability in the acid environment, acting porphyrin as a catalyst to the passage of protons through the film, reducing its electrochemical impedance up to 7 orders of magnitude with respect to the compounds nylon/H2T(p-NH2)PP and nylon/GO. Likewise, good capacitance values are also shown by modifying the concentrations of porphyrin and GO reinforcing materials. These properties are important for technological applications, such as anticorrosion coating for bipolar plates or membrane in a fuel cell type PEM, super-capacitors, etc.

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Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

Engineering and Technology Journal ◽

10.30684/etj.v38i4a.351 ◽

2020 ◽

Vol 38 (4A) ◽

pp. 491-500

Author(s):

Abeer F. Al-Attar ◽

Saad B. H. Farid ◽

Fadhil A. Hashim

Keyword(s):

Ionic Conductivity ◽

Electrochemical Impedance ◽

Structural Information ◽

Impedance Analysis ◽

High Energy ◽

Yttria Stabilized Zirconia ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

Powder Morphology ◽

X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

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Ferromagnetic Resonance in Metal–Dielectric and Metal–Carbon Composite Films

Bulletin of the Russian Academy of Sciences Physics ◽

10.3103/s106287382009021x ◽

2020 ◽

Vol 84 (9) ◽

pp. 1065-1067

Author(s):

L. N. Kotov ◽

M. P. Lasek ◽

V. K. Turkov ◽

D. M. Kholopov ◽

V. S. Vlasov ◽

...

Keyword(s):

Ferromagnetic Resonance ◽

Composite Films ◽

Carbon Composite

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Deposition and Tribological Properties of CVD Diamond/Diamond-Like Carbon Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.565.615 ◽

2012 ◽

Vol 565 ◽

pp. 615-620

Author(s):

Bin Shen ◽

Liang Wang ◽

Su Lin Chen ◽

Fang Hong Sun

Keyword(s):

Surface Morphology ◽

Composite Film ◽

Tribological Properties ◽

Composite Films ◽

Cvd Diamond ◽

Carbon Composite ◽

Dry Sliding ◽

Diamond Like Carbon ◽

Dlc Film ◽

Bonding State

The CVD diamond/diamond-like carbon composite film is fabricated on the WC-Co substrate by depositing a layer of Diamond-like Carbon film on the surface of conventional Micro- or Nano-crystalline diamond film. The hot filament chemical vapor deposition (HFCVD) method and vacuum arc discharge with a graphite cathode are adopted respectively to deposit the MCD/NCD and DLC films. A variety of characterization techniques, including filed emission scanning electron microscope (FE-SEM) and Raman spectroscopy are employed to investigate the surface morphology and atomic bonding state of as-deposited MCD/DLC and NCD/DLC composite film. The results show that both MCD/DLC and NCD/DLC composite films present similar surface morphology with the MCD and NCD films, except for scattering a considerable amount of small-sized diamond crystallites among the grain boundary area. The atomic-bonding state of as-deposited MCD/DLC and NCD/DLC composite films is determined by the top-layered DLC film, which is mainly consisted of amorphous carbon phase and no discernible sp3 characteristic peak can be observed from their Raman spectrum. Furthermore, the tribological properties of as-deposited MCD/DLC and NCD/DLC composite films is examined using a ball-on-plate reciprocating friction tester under both dry sliding and water-lubricating conditions, comparing with conventional DLC, MCD and NCD films. Silicon nitride balls are used as counterpart materials. For the CVD diamond/DLC composite films, the self-lubricating effect of top-layered DLC film is beneficial for suppressing the initial friction peak, as well as shortening the run-in period. The average friction coefficients of MCD/DLC and NCD/DLC composite films during stable sliding period are 0.07 and 0.10 respectively in dry sliding; while under water-lubricating condition, they further decreases to 0.03 and 0.07.

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Hierarchically Porous Silk/Activated-Carbon Composite Fibres for Adsorption and Repellence of Volatile Organic Compounds

Molecules ◽

10.3390/molecules25051207 ◽

2020 ◽

Vol 25 (5) ◽

pp. 1207

Author(s):

Aled D. Roberts ◽

Jet-Sing M. Lee ◽

Adrián Magaz ◽

Martin W. Smith ◽

Michael Dennis ◽

...

Keyword(s):

Activated Carbon ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Carbon Composite ◽

Hierarchically Porous ◽

Surface Areas ◽

Regenerated Silk Fibroin ◽

Volatile Organic ◽

Fibre Spinning ◽

Solution Blow Spinning

Fabrics comprised of porous fibres could provide effective passive protection against chemical and biological (CB) threats whilst maintaining high air permeability (breathability). Here, we fabricate hierarchically porous fibres consisting of regenerated silk fibroin (RSF) and activated-carbon (AC) prepared through two fibre spinning techniques in combination with ice-templating—namely cryogenic solution blow spinning (Cryo-SBS) and cryogenic wet-spinning (Cryo-WS). The Cryo-WS RSF fibres had exceptionally small macropores (as low as 0.1 µm) and high specific surface areas (SSAs) of up to 79 m2·g−1. The incorporation of AC could further increase the SSA to 210 m2·g−1 (25 wt.% loading) whilst also increasing adsorption capacity for volatile organic compounds (VOCs).

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Enhanced electrochemical performances of activated carbon (AC)-nickel-metal organic framework (SIFSIX-3-Ni) composite and ion-gel electrolyte based supercapacitor

Carbon letters ◽

10.1007/s42823-020-00218-x ◽

2021 ◽

Author(s):

Kyu Seok Lee ◽

Ye Ji Seo ◽

Hyeon Taek Jeong

Keyword(s):

Activated Carbon ◽

Electrochemical Impedance ◽

Metal Organic Framework ◽

Gel Electrolyte ◽

Electrochemical Performances ◽

Galvanostatic Charge ◽

Nickel Metal ◽

Capacitive Behavior ◽

Metal Organic ◽

Ion Gel

AbstractIn this study, we investigated that the activated carbon (AC)-based supercapacitor and introduced SIFSIX-3-Ni as a porous conducting additive to increase its electrochemical performances of AC/SIFSIX-3-Ni composite-based supercapacitor. The AC/SIFSIX-3-Ni composites are coated onto the aluminum substrate using the doctor blade method and conducted an ion-gel electrolyte to produce a symmetrical supercapacitor. The electrochemical properties of the AC/SIFSIX-3-Ni composite-based supercapacitor are evaluated through cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge tests (GCD). The AC/SIFSIX-3-Ni composite-based supercapacitor showed reasonable capacitive behavior in various electrochemical measurements, including CV, EIS, and GCD. The highest specific capacitance of the AC/SIFSIX-3-Ni composite-based supercapacitor was 129 F g−1 at 20 mV s−1.

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