Search

Charge-discharge processes of supercapacitor with carbon black KJEC 600/Li in non-aqueous electrolyte: 1 M LiPF6 in a mixture of ethylene carbonate (1/3), diethyl carbonate (1/3), dimethyl carbonate (1/3) are investigated. Galvanostatic cycling was carried out in the range from 1 to 4 V with currents from 100 to 5000 mA/g of carbon black. The maximum discharge capacity of 196 F/g has been reached. The porous structure and hydrophilic-hydrophobic properties of carbon black KJEC 600 were investigated by the standard contact porosimetry method (MSCP). The following values were obtained: total specific surface area of 2500 m2/g, total porosity of 7.8 cm3/g, hydrophilic porosity of 4.9 cm3/g, hydrophobic porosity of 2.9 cm3/g. The obtained experimental dependence of the energy efficiency has a maximum (80%) at a current of 250 mA/g. Mathematical modeling of charge-discharge processes of the supercapacitor is developed with taking into account the charging of the double electric layer (EDL) and adsorption of lithium ions according to the Butler-Volmer equation and the Frumkin isotherm for the carbon electrode are taken into account. From the comparison of the calculated and measured charge-discharge curves it follows that these curves are satisfactorily consistent with each other, which indicates the correctness of the model. The density of the exchange current and the specific capacitance of the EDL refereed to the true surface found by the fitting are equal to i 0,ad = 2.8 × 10−29A/сm2 and C dl = 3.5 μF/сm2 respectively. On the basis of the developed model for different specific currents the energy efficiency dependences on the exchange current density of the adsorption reaction were calculated. Interestingly, these dependencies have a minimum. Based on the model, the profiles of the potential the surface coverage of lithium ions were also calculated. • Charge-discharge processes of supercapacitor in non-aqueous electrolyte are studied. • The porous structure of carbon electrode was investigated by the reference contact porometry method. • Frumkin adsorption isotherm for the carbon electrode are taken into account. • The calculated and measured charge-discharge curves are consistent with each other. • Energy efficiency dependences on the exchange current density were calculated. [ABSTRACT FROM AUTHOR]

The development of efficient and cost-effective water splitting electrolyzers is a fundamental step to support the achievement of climate neutrality by using renewable energy sources to produce green H 2 as a form of clean fuel. In this work, we investigated Pt-based nanostructured cathodes for high-performance alkaline electrolyzers (AELs), showing the beneficial effect of graphene over traditional carbon black as nanocatalysts support. By relying on a water-based, scalable, synthetic method, surface-cleaned Pt nanoparticles were successfully produced and strongly anchored to defect-free graphene flakes, the latter produced through wet-jet milling exfoliation of natural graphite. Once deposited on conventional gas diffusion layers, Pt/graphene catalysts outperform traditional Pt on Vulcan (Pt/C) in terms of hydrogen evolution reaction (HER) activity and performance durability. The two-dimensional morphology of graphene flakes strongly retains the catalysts in the electrode even in the absence of any binder, while intrinsically ensuring the exposure of the catalytic sites for the HER. This rationale enables the fabrication of high-performance AELs based on Pt/graphene cathodes. By using commercially available cost-effective anodes (stainless-steel meshes), our AELs reached current densities of 1 A cm−2 at a voltage of as low as 1.71 V. These AELs can even operate up to more than 2 A cm−2 (e.g., 2.2 A cm−2 at 1.90 V), with stable performance during accelerated stress tests. Our study discloses two main aspects: (1) graphene is an effective conductive support for 1–10 nm-scale catalysts for the development of nanostructured cathodes with elevated catalytic properties and durable performance; (2) the use of efficient nanostructured cathodes can boost the AEL's performance to state-of-the-art values reported for proton-exchange membrane electrolyzers, avoiding the use of expensive anodes (e.g., Ir-based ones). [ABSTRACT FROM AUTHOR]

Abstract Porous graphene nanoribbons are synthesized via an effective and template-free method based on introducing of carbon black (CB) into the graphene oxide (GO) layers, and then, thermal exfoliation under hydrogen plasma (H 2) stream (PGNRs/CB). The nanocomposites are transferred onto the glassy carbon electrode surface (GCE) and tested directly for charge storage intentions or further modified with Pt-Ru alloy nanoclusters and examined for electrooxidation of methanol. The physicochemical characteristics and electrochemical activities of composites are studied by several surface techniques and electrochemical methods. A remarkable specific capacitance (223.0 F g−1 at 1.0 A g−1) is achieved for PGNRs/CB electrode, compared with 137.2 and 67.6 F g−1 values obtained for porous graphene nanoribbons (PGNRs) and graphene nanosheets (GNs-Ar) formed in the presence of H 2 plasma and pure argon streams, respectively. The capacitance retention remained at more than 91% even after 5000 cycles. The supercapacitive behavior and excellent durability achieved for PGNRs/CB materials are attributed to the (i) large surface area of PGNRs obtained by annealing in H 2 plasma, and thus, the increased ion accessibility of graphene system, and (ii) stability against the restacking of the PGNRs achieved in the presence of CB. In addition, the GCE-PGNRs/CB was successfully used as a favorable support and further modified with Pt-Ru alloy nanoclusters via electrodeposition. The GCE-PGNRs/CB/Pt-Ru showed an excellent electrocatalytic activity, high resistance against poisoning effect of CO and good stability toward oxidation of methanol. The experimental results are presented and discussed, regarding charge storage and electrocatalytic oxidation of methanol. Graphical abstract Image 1 Highlights • Porous graphene nanoribbons/carbon black, 1062 m2g–1, thermally fabricated in H 2 -plasma. • The PGNRs/CB electrode showed a large specific capacitance, 223.0 F g−1 at 1.0 A g−1. • GC-PGNRs/CB was successfully modified with Pt-Ru metal alloy nanocluster. • GC-PGNRs/CB/Pt-Ru electrode showed excellent activity & stability for CH 3 OH oxidation. [ABSTRACT FROM AUTHOR]

A cost effective, low temperature, scalable route is presented for the synthesis of Selenium nanoparticles-cetyltrimethylammonium bromide-decorated multiwalled carbon nanotubes (Se NPs@CTAB-MWCNTs) composite. The Se content in the carbon black (CB) free Li-Se NPs@CTAB-MWCNTs cell is ∼72 wt%, which is much higher than that reported in previous studies on Li-Se composite cells, where the Se loadings typically vary between 40 and 50 wt% in full cells. The high loading of Se imparts a high capacity to the composite cell due to a high electrical conductivity of Se NPs (∼0.1 S cm −1 ). The initial Li-ion storage capacity delivered by the same CB free cell is ∼709 mAh g Se −1 (at 0.5 current (C)-rate), and a reversible capacity of 157 mAh g Se −1 is retained after 500 cycles. In comparison, the reversible capacities offered by the Li-Se NPs-CB cell (at 80 wt% Se loading), and the Li-Se NPs@CTAB-MWCNTs-CB cell (at 64 wt% Se loading) are 13.8 and 172.5 mAh g Se −1 at the same C-rate, after 500 cycles. For the CB free cell, the capacity decay is 0.14% per cycle from 8th to 500 th cycle. Though present in small quantities of 18 and 16 wt% in the two composite based cells without and with CB, CTAB-MWCNTs confer the following functional attributes to the cells. They (a) restrict polyselenide shuttle, (b) buffer the volume expansion during discharge and (c) allow Li-ion storage, without the use of any conducting CB additive (due to the composite's high inherent electrical conductivity). The electrochemical performance of the CB free Li-Se composite cell opens up opportunities to develop eco-friendly and robust Li-Se batteries. [ABSTRACT FROM AUTHOR]

Design of sensors with improved parameters is still an extensive field of analytical research. A comparative study between seven types of all-solid-state ion-selective electrodes (ASS-ISEs) and coated disc ion-selective electrode (CD-ISE) was carried out. This work developed solid contact layers designed from molecular organic materials (MOMs): tetrathiafulvalene (TTF), its chloride salt (TTFCl) or tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) with or without the addition of carbon black (CB) acting as inner transducers. Intermediate layers were deposited by a solution casting on the top of glassy carbon disc electrodes and then were covered with a membrane containing tridodecylmethylammonium chloride, o-nitrophenyl octyl ether, and poly(vinyl chloride). Molecular organic conductive materials were compared with CB-MOM composites as materials responsible for transduction process in all-solid-state chloride-selective electrodes. The proposed solid contact layers were characterized by scanning electron microscopy and electrochemical methods. The intermediate layer effect on the electrodes was tested, and prepared sensors were investigated by potentiometric, chronopotentiometric and electrochemical impedance spectroscopy measurements. All the modified electrodes displayed a satisfactory performance and Nernstian electrode function for chloride in the concentration range from 10 −5  M to 10 −1  M, however the best sensitivity and detection limit were observed for the CB-TTFCl-contacted electrode. The obtained results showed that the electrodes with internal layer consisting of CB-MOM nanocomposite presented slightly more sensitive response to chloride, lower impedance and a higher capacitance than electrodes based only on various molecular organic materials. [ABSTRACT FROM AUTHOR]

The cost of platinum (Pt) counter electrode (CE) accounts for over 40% of the total cost of a dye sensitized solar cell (DSSC), thus replacing Pt with a cheaper material can significantly reduce the overall cost of the device. To this end, a novel cost-effective mesoporous carbon black (CB)/polyaniline nanotube (PAniNT) nanocomposite was fabricated as a potential CE material. The nanocomposite, prepared by chemical oxidation polymerization of aniline in the presence of CB, was characterized by Fourier transform infra-red spectroscopy, Raman spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Different amount of CB were added in the polymer matrix to optimize the electro-catalytic activity of the CB/PAniNT nanocomposite towards reduction of I 3 − to I − . Cyclic voltammetry, current density-voltage measurements, electrochemical impedance spectroscopy and Tafel plot analysis showed that incorporation of CB resulted in an augmented active catalytic surface area and enhanced charge transfer from CE to the electrolyte. These factors contributed towards achieving a high performance DSSC with efficiency of 6.62% in liquid electrolyte (LE) and 4.82% in polymethyl methacrylate based polymer gel electrolyte (PGE) under irradiation of light (100 mW cm −2 ). Furthermore, the effect of CE thickness was also studied in detail and the cell performance was found to improve proportionally with growing thickness. An optimized device was finally assembled with a 10.58 μm thick 0.75 wt% CB/PAniNT nanocomposite film as CE corresponding to J SC , V 0C and R CT values of 12.52 mA cm −2 , 0.74 V and 0.99 Ω for LE, and 9.11 mA cm −2 , 0.74 V and 1.30 Ω for PGE respectively. [ABSTRACT FROM AUTHOR]

The recently launched concept of Semi-Solid Flow Batteries (SSFBs) shows a strong potential for flexible energy storage, but the liquid-dispersed state of the electrode materials introduces several aspects of which a scientific understanding is lacking. We studied the effect of electrochemical cycling on the rheological and electrical properties of a SSFB anolyte containing Li 4 Ti 5 O 12 (LTO) and Ketjen Black (KB) particles in EC:DMC solvent with 1 M LiPF 6 , using an adapted rheometer that allows in situ electrochemical cycling and electrical impedance spectroscopy. Charging (lithiation) caused a reduction in the electronic conductivity, yield stress and high shear viscosity of the fluid electrode. For mildly reducing voltages (1.4 V), these changes were partially reversed on discharging. For more reducing voltages these changes were stronger and persistent. The finding of comparable trends for a fluid electrode without the LTO, lends support to a simplistic interpretation, in which all trends are ascribed to the formation of a surface layer around the conductive KB nanoparticles. This Solid Electrolyte Interphase (SEI) insulates particles and reduces the van der Waals attractions between them. SEI layers formed at less reducing voltages, partially dissolve during the subsequent discharge. Those formed at more reducing voltages, are thicker and permanent. As these layers increase the electronic resistance of the fluid electrode by (more than) an order of magnitude, our findings highlight significant challenges due to SEI formation that still need to be overcome to realize SSFBs. [ABSTRACT FROM AUTHOR]

Iron hydroxyl phosphate hydrate Fe 1.19 (PO 4 )(OH) 0.57 (H 2 O) 0.43 (FPHH) was obtained by hydrothermal synthesis at 220 °C for 6 hours. Addition of carbon black to the solution before hydrothermal treatment led to a reduction of the FPHH particle size from ∼10 μm in the carbon-free compound to ∼300–500 nm in the FPHH-10%C and FPHH-20%C composite with a good dispersion of conducting carbon black. X-ray diffraction, 57Fe Mossbauer spectroscopy and a thermal decomposition study showed that the addition of carbon black did not interfere with the formation of the FPHH phase. Thanks to its favorable microstructural characteristics, the FPHH-10%C and FPHH-20%C material exhibited good performance as positive electrode for Li-ion battery, with high initial discharge capacities of 150, 128 and 112 mAh g −1 at 0.25C, 0.5C and 1C rates respectively and 99% capacity retention after 150 cycles at 2C. These results show that addition of solid carbon directly into the solution prior to hydrothermal treatment is a simple and effective way to reduce particle size and also to improve electronic conductivity by dispersing conductive carbon around the active material. This approach is easily transferable to other compounds prepared by hydrothermal synthesis, in order to control particle size while retaining the advantage of crystallization at low temperature. [ABSTRACT FROM AUTHOR]

We report the facile in situ chemical oxidative synthesis and detailed electrochemical evaluation of polyindole (PIn) and its composites with carbon black (CB) and molybdenum disulfide (MoS 2 ) for application in supercapacitor as an electrode material. PIn, owing to its unique property of possessing a fused benzene and a pyrrole ring, proves to be a very interesting material. Material design involves incorporation of conducting CB and sheet like MoS 2 into the PIn matrix in order to promote charge transportation. This results into the PIn/CB/MoS 2 ternary composite with improved electrochemical performance. PIn/CB/MoS 2 -2 exhibits a gravimetric capacitance of 442 F g −1 and a volumetric capacitance of 512.7 F cm −3 at the current density of 1 A g −1 . Additionally, it exhibits a high coulombic efficiency of 96.7% at the current density of 10 A g −1 together with a long term cyclic life (92.3% capacitance retention after 5000 cycles at 10 A g −1 ). Hence, PIn/CB/MoS 2 -2 composite proves to be very effective with fairly improved gravimetric and volumetric performances as an electrode material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

A flexible and free-collector-current of silicon-based anode is facilely prepared just by coating carbon black (CB) and silicon powders layer-by-layer. The resultant electrodes with a “sandwich” structure (CB/Si/CB) are assembled into half-cell and its electrochemical properties are tested. This type of anode exhibits excellent cycling and outstanding rate capability. The superior electrochemical performances are ascribed to both flexible CB-layers to offset the volume expansion of Si-particle. And, the CB-layer with high electric conductivity can provide efficient electron conductive pathways when Si particles react with lithium. More importantly, the CB/Si/CB electrodes without the collerctor (copper-foil) are exhibited high energy density, due to the weight proportion of copper foil is exceeded 60%. The CB/Si/CB electrode is used to assemble full-cell with the same structure as free-collector LCO/CB cathode material. It imposes the energy density of 200 Wh kg −1 , and can keep stable charging-discharging capability at various deformations of shapes. And the flexible-cell of high performance is obtained to meet diverse applications in energy storage devices. Until now, many flexible batteries are put forward by researchers, but these product is faced with the complex production-process, high-cost material, low energy-density. This CB/Si/CB structure is produced with the matching current manufacturing industry and the common raw material, and to get a full-cell of the high energy density. [ABSTRACT FROM AUTHOR]

Highly selective, sensitive and low potential detection of biological analytes by simple and rapid electrochemical technique using low cost nanocarbons is a demanding research since last decade. Herein, we report a low cost, new, nanocarbon, the carbon black (CL-08) functionalized with syringic acid (SA) modified glassy carbon electrode (GCE) for selective L-cysteine (L-CySH) electrocatalysis at 0.04 V vs Ag/AgCl. The new matrix is competitive in the low potential L-CySH detection compared to the multiwalled carbon nanotube, graphite powder, carbon mesoporous and graphitized mesoporous carbon. The possible in situ generated redox products namely 2,6-dimethoxy benzoquinone and 3,4-dihydroxy-5-methoxy benzoic acid were proposed to form on the GCE/SA@CL-08 with two electron transfer and nernstian behaviours. FTIR and UV–vis analyses collectively revealed the presence of quinone species. The GCE/SA@CL-08 showed L-CySH electrocatalysis with good selectivity, 0.42 nA.μM −1 and 5.4 nA.μM −1 sensitivity in the detection range of 20–100 μM and 100–1000 μM respectively with 639 nM limit of detection, in chronoamperometry. A successful demonstration of L-CySH detection from the simulated blood serum and processed chicken samples with substantial recovery values using the GCE/SA@CL-08 were presented in this study. [ABSTRACT FROM AUTHOR]

• Development of flexible nanocellulose-based carbon black@polyaniline electrodes. • Enhancement of the specific capacity and cycling stability by nanostructuring of PANI. • Green and cost-effective way to prepare high-performance pseudocapacitive electrode. Flexible, lightweight and electrically conductive composites based on renewable resources have recently attracted a growing interest for the development of high performance sustainable energy storage devices that can meet the needs of modern wearable and portable electronics. Herein, we developed a high performance carbon black@polyaniline (PANI) based flexible electrodes using a facile, low cost and environmentally friendly strategy. The strategy consisted of a co-deposition and nanostructuring of PANI layer with tailored morphology on the surface of carbon black and nanofibrillated cellulose (NFC) via in situ polymerization. NFC acted as a mechanical skeleton and imparted the electrode with strength and flexibility to ensure excellent electrochemical performance. The co-doping of PANI chains via a combination of a primary/secondary dopant, namely, HCl/poly(2-acrylamido-2-methyl-1-propanesulfonic acid), was used to control the morphology of PANI. Correlation between the textural properties of the carbon black, NFC loading, and the properties of the resulting electrodes was established. The maximum specific capacitance of 363±9 F/g at the potential scan rate of 50 mV/s was exhibited by the electrode with 60% of active material loading, for which an effective growth of hierarchical nanostructures of carbon black@PANI on the surface of NFC was achieved, leading to the highest specific surface area of the composite (861 m2/g) and a to a microporosity/mesoporosity balance. The remarkable cycling stability of the hybrid electrodes was attained as the specific capacitance retention was close to 100% with a negligible capacity decay within the tested period (over 500 cycles) regardless of the amount of the active material. This study provides an eco-friendly and cost-effective way to prepare high performance flexible electrodes for pseudo-capacitors [Display omitted] [ABSTRACT FROM AUTHOR]

This work aims at better understanding the interactions existing between the liquid electrolyte and the solid composite electrode in a Li-ion battery. We substituted the common active material (e.g. LiNi 1/3 Mn 1/3 Co 1/3 O 2 or LiFePO 4) by an insulating (inactive) γ-Al 2 O 3 compound in order to detect and evidence the interaction between the carbon black electronic additive and the liquid electrolyte. Our study presents the characterization of charge (electrons and ions) transport at different scales by combining a high-frequency analysis performed by broadband dielectric spectroscopy (BDS, up to 1010 Hz), along with a low-frequency analysis performed by electrochemical impedance spectroscopy (EIS, down to 10−3 Hz). Two carbon black materials with two different specific surface areas (80 m2.g−1 and 65 m2.g−1, respectively) were studied. The electronic percolation threshold and the kinetics of impregnation of the hierarchical composite electrode by the liquid electrolyte have been determined with respect to the carbon black content. The significant influence of the adsorbtion of ions at the carbon black surface on the electrons transport is particularly highlighted and explained. [ABSTRACT FROM AUTHOR]

The surface modification of the stainless steel mesh (SSM) was conducted by acid etching, binder-free carbon black (CB) coating and the low-temperature heat treatment below 400 °C to improve the microbial bioelectrocatalytic activity for use as high-performance anode in microbial fuel cells. The modified SSM, such as SSM/CB-400, could generate a high current density of up to 1.91 mA cm −2 , which was nearly three orders of magnitude higher than the untreated SSM electrode (0.0025 mA cm −2 ). Moreover, it was stable and recovered the equal current density after removal of the formed biofilms. Surface characterization results demonstrate that the performance improvement was attributed to the CB/Fe 3 O 4 composite layer formed onto the surface of the SSM, which protected the biofilms from being poisoned by the Cr component in the SSM and ensured a rapid electron transfer from biofilms to the SSM surface. The CB/Fe 3 O 4 composite layer showed excellent corrosion-resistant under the oxidizing potential of + 0.2 V (vs. Ag/AgCl). Rising the heating temperature to 500 °C, the SSM-500 and SSM/CB-500 electrodes suffered from corrosion due to the formation of α-Fe 2 O 3 crystals. [ABSTRACT FROM AUTHOR]

A facile “one-step” route to produce a homogenous and highly stable cobalt phthalocyanine (CoPc)-based dispersion by using carbon black (CB) as supporting material is reported. Herein, CB is proposed as effective material to load CoPc in order to obtain a CB/CoPc hybrid nanocomposite dispersion suitable for modifying screen-printed electrodes (SPEs) by an easy and automatable drop casting approach. CoPc resulted anchored to CB by a non-covalent physisorption, confirmed by IR and UV-visible spectroscopies, allowing to preserve the electrochemical performances of CoPc. The resulting CB/CoPc-modified SPE was tested as sensing tool to detect thiocholine, an enzymatic product of butyrylcholinesterase (BChE). The use of CB/CoPc leads to a highly sensitive thiocholine detection by applying a low potential (+0.05 V vs. internal reference) without fouling problem, a typical drawback that affects the thiol electrochemical detection. The favorable characteristics of the sensor were exploited for an easy BChE biosensor fabrication that renders this biosensor well suitable for mass-production. This electrochemical monoenzymatic biosensor was then challenged towards paraoxon, chosen as model organophosphorous pesticide, obtaining a low detection limit (18 nM). The suitability of the biosensor was tested in a waste water sample obtaining satisfactory recovery values, thus demonstrating its capability in such complex matrix. [ABSTRACT FROM AUTHOR]

Hybrid nanostructures with reliable electrochemical performances (e.g., high rate capability and long cycling lifetime) and low fabrication costs are attractive for extensive application for next-generation energy storage devices. Herein, based on the inexpensive commercial carbon black (CB), a ternary manganese ferrite/carbon black/polyaniline (MCBP) hybrid is designed and synthesized through a facile two-step approach. It is found that the synergistic effects in this strongly coupled ternary hybrid nanostructure can remarkably enhance the electrochemical performances, including the impressively high rate capability (∼98% capacitance retention at a current density of as high as 40 A g −1 ) and excellent cycling stability (∼80% capacitance retention after 10,000 cycles at 5 A g −1 ). A symmetric supercapacitor is fabricated using ternary MCBP hybrid, which presents excellent rate capability (over 94% capacitance retention at 10 A g −1 ) and long cycle life (∼75% capacitance retention after 100,000 cycles at 5 A g −1 ). Such a low-cost integrated ternary hybrid is a promising electrode material for commercial applications in supercapacitors. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide/manganese dioxide/carbon black (rGO/MnO 2 /CB) ternary film is prepared by a simple vacuum filtration method. MnO 2 nano particles grow on both sides of the graphene layers serving as active sites for the electrochemical reactions which remarkably enhance the specific capacitance. While CB acts as spacers between the graphene layers preventing the restacking of graphene sheets and improves the conductivity between the basal planes of graphene sheets, leading to a better rate performance. Thanks to the synergistic effects of CB and MnO 2 , the capacitanceis improved to 209 F g −1 , which is much better than that of the binary graphene/CB film (96 F g −1 ) and maintains at 77 F g −1 even at a fastscan rate of 1 V s −1 . The 1.8 V aqueous asymmetric supercapacitor based on rGO/MnO 2 (2.5)/CB (positive electrode) and rGO/CB (negative electrode) exhibits a large energy density of 24.3 Wh kg −1 especially a high power delivery capability with an energy density of 10 Wh kg −1 at the power density of 45 kW kg −1 . Furthermore, the energy density of the flexible solid-state asymmetric device based on this ternary film reaches 20 Wh kg −1 and maintains 10 Wh kg −1 at the power density of 21 kW kg −1 . [ABSTRACT FROM AUTHOR]

To realize a high catalyst utilization, better fuel cell performance and durability as well as low production cost, an efficient design strategy of the catalyst layer that can improve both the oxygen accessibility and structure stability is highly required. Here, we describe the preparation of fuel cell electrocatalysts with an efficient fuel cell performance and better stability based on hybrids of multi-walled carbon nanotubes (MWNTs) and carbon black (CB) which were wrapped by a proton conducting polymer, poly[2,2′-(2,6-pyridine)-5,5′-bibenzimidazole], before deposition of the platinum (Pt) metal catalyst. The catalyst mass activity after feeding only 10%-MWNTs to CB increased by 1.5 and 2 times than those of the MWNTs-based- and CB-based catalysts, respectively. The results also demonstrated that 90 wt% of the MWNTs in the catalyst layer allows it to be replaced by CB without any significant change in its durability and performance under 120 °C and non-humidified condition. [ABSTRACT FROM AUTHOR]

Highly micro-mesoporous carbon electrodes have been synthesized by the polycondensation of resorcinol-formaldehyde-melamine mixtures in the presence of a carbon conductive additive. The materials showed high surface functionalization (N- and O- groups) provided by the precursors. Despite the low amount used, the conductive additive had a marked effect on the porosity of the aerogels; for a given series, the carbon black loaded materials showed similar micropore volumes and a more developed mesoporosity than the pristine aerogels. Furthermore, the activation treatment under CO 2 atmosphere led to an increase in the surface area along with a widening of the mesoporosity. The synthesized aerogels were explored as electrodes for the electro-assisted removal of sodium chloride from saline water. A desalting capacity of 7.3 mg/g was obtained for monolith electrodes of sample MRF-Act/CB, along with an excellent chemical stability upon charge and discharge at high polarization voltages. Such good electrochemical performance is due to the combination of an adequate pore network and surface functionalization with an enhanced electrical conductivity achieved upon the incorporation of the carbon black additive during the polycondensation of the aerogel precursors. [ABSTRACT FROM AUTHOR]

A hybrid-direct carbon fuel cell (HDCFC), consisting of a molten slurry of solid carbon black and (Li-K) 2 CO 3 added to the anode chamber of a solid oxide fuel cell, was characterized using current-potential-power density curves, electrochemical impedance spectroscopy, and cyclic voltammetry. Two types of experimental setups were employed in this study, an anode-supported full cell configuration (two electrodes, two atmospheres setup) and a 3-electrode electrolyte-supported half-cell setup (single atmosphere). Anode processes with and without catalysts were investigated as a function of temperature (700–800 °C) and anode sweep gas (N 2 , 4–100% CO 2 in N 2 -CO 2 ). It was shown that the addition of silver based catalysts (Ag, Ag 2 O, Ag 2 CO 3 ) into the carbon-carbonate slurry enhanced the performance of the HDCFC. [ABSTRACT FROM AUTHOR]

Pt-Mn 3 O 4 catalysts with carbon black as conductive agent and support show a remarkable activity for oxygen evolution reaction because of a synergistic effect between Pt and Mn 3 O 4 . The Pt-Mn 3 O 4 /C catalyst with a weight ratio of Pt to Mn 3 O 4 of 3:1 gives the best performance. After loading with Mn 3 O 4 , the binding energy value of Pt 4f and Mn 2p respectively has a positive and negative shift, which will accelerate to form a Pt-OH bond of the active centres. [ABSTRACT FROM AUTHOR]

A novel and sensitive electrochemical sensor for bisphenol A (BPA) determination based on carbon black supporting ferroferric oxide nanoparticles (Fe 3 O 4 NPs-CB) was developed. The Fe 3 O 4 NPs-CB nanocomposite fabricated on the glassy carbon electrode (GCE) demonstrated a high electrocatalytic activity towards the oxidation of BPA. The oxidation overpotentials of BPA decreased significantly and the peak current increased greatly compared with those of Fe 3 O 4 NPs- or CB-modified or bare GCE. Differential pulse voltammetry (DPV) was used as a sensitive analytical method for the determination of BPA, and a much wider linear dynamic range of BPA determination was found between 0.1 nM and 50 μM. The limit of detection (LOD) for BPA was found down to 0.031 nM based on S / N = 3. Fabricated Fe 3 O 4 NPs-CB nanocomposite on GCE displayed several outstanding properties such as good stability, high sensitivity and remarkable repeatability. The described sensor has been used for the determination of BPA in water samples with good recovery, ranging from 93.2% to 104.1%. Additionally, the migration of BPA from PC drinking bottles was evaluated by using water to simulate migration into aqueous and acidic foods. [ABSTRACT FROM AUTHOR]

Sulfur doped graphene nanosheets (S-GNs) are synthesized by using graphene oxide (GO) as carbon source and sodium polysulfide as sulfur source, and then, annealing the prepared precursors (S-GO) at different temperatures up to 1000 °C. The structure and morphological characteristics of the fabricated composites are investigated by Field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical methods. Electrochemical results show that S-GNs has high catalytic activity toward oxygen reduction reaction (ORR) in an alkaline electrolyte in comparison with GNs. To improve the characteristics of S-GNs and prevent agglomeration of the particles, the S-GNs-1000-CB is fabricated by mixing the S-GNs-1000 with the carbon black (CB). The results show that CB particles inserted between S-GNs layers function as spacers and prevent the restacking of S-GNs during drying, and thus, most probably promote the diffusion of O 2 molecules through S-GNs and enhance the ORR rate. The S-GNs-1000-CB composites show excellent electrocatalytic activity in alkaline solutions over all the studied (catalyst) samples. Our findings demonstrate that S-GNs-1000-CB is an appropriate catalyst for ORR in alkaline solutions, and could be a good candidate for replacement of the precious Pt based catalysts for this goal. [ABSTRACT FROM AUTHOR]

As a novel anode material for lithium-ion batteries, Pb(NO3)2can deliver an initial discharge capacity as high as 1310.8 mAh g−1. However, its capacity retention is poor upon repeated cycles. In this work, carbon black (CB), graphene (GN) and carbon nanotube (CNT) are used as conductive additives to fabricate Pb(NO3)2/CB, Pb(NO3)2/GN and Pb(NO3)2/CNT, respectively. It is observed that CB and GN fail to form uniform three-dimensional conductive network for Pb(NO3)2. As a result, Pb(NO3)2/CB and Pb(NO3)2/GN do not show obviously improved electrochemical properties compared to bare Pb(NO3)2. For comparison, CNTs provide cross-linking conductive cages for Pb(NO3)2particles. It can be found that CNT coating can significantly enhance the electrochemical property of Pb(NO3)2. Pb(NO3)2/CNT reveals a reversible charge capacity of 495.2 mAh g−1after 45 cycles at a current density of 50mAg−1, which is much higher than that of bare Pb(NO3)2(227.4 mAh g−1), Pb(NO3)2/CB (278.0 mAh g−1), Pb(NO3)2/GN (327.2 mAh g−1). Even cycled at 200mAg−1, Pb(NO3)2/CNT can maintain a reversible lithium storage capacity of 411.7 mAh g−1. All these results suggest that Pb(NO3)2/CNT is a promising anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Thermoplastic carbon composite electrodes have been introduced by our group as novel electrodes with improved electrochemical properties and previously applied for accurate detection of biomarkers using voltammetric methods. Because of their exceptional properties, we hypothesized they would work well as potentiometric ion-selective electrodes as well. In this work, potassium selective thermoplastic electrodes (TPEs) were developed for potentiometric detection for the first time and applied in biofluids. TPEs were fabricated using mixture of polystyrene and polycaprolactone and two types of graphite (MG1599 and Nano19) for comparison, and modified with carbon black via drop-casting. Carbon black modification was optimized in the presence of various numbers of carbon black layers, while ion selective membrane components were optimized at different component ratios. Under optimized conditions, TPEs exhibited Nernstian response to K + with sensitivity of 59.3 ± 1.01 mV decade−1 and near-Nernstian response with sensitivity of 56.8 ± 1.7 mV decade−1 within a linear range of 1.0 × 10−4 M-1.0 × 10−1 M with a LOD of 1.0 × 10−4- M for Nano19- and MG1599-based TPEs, respectively. The K +-selective TPEs demonstrated rapid response (4 s) and excellent stability, repeatability and reproducibility. The applicability of electrodes were shown in human pooled urine and artificial interstitial fluid samples with potassium ion concentrations ranging from healthy and unhealthy levels. Therefore, the electrodes could be used in healthcare applications for accurate detection of K + exists in complex matrix and can be easily adapted to simultaneously monitor other ions for diagnosis of diseases due to miniaturization of TPEs. [Display omitted] [ABSTRACT FROM AUTHOR]

Ultrahigh power is needed beyond the state-of-the-art supercapacitors for emerging technologies. Towards this goal, nanostructured carbon materials have been extensively studied but unfortunately encountered with the difficulty in practical applications, which is largely due to their limited packing densities. In this work, we utilize a highly dense commercial activated carbon to develop high-rate nanocomposite electrodes and ultrahigh-power supercapacitors by compositing activated carbon with carbon nanomaterials, including zero-dimensional carbon black, one-dimensional carbon nanotube, and two-dimensional graphene. Enabled by the mixed packing (forming a unique point-to-line-to-plane contact morphology), diverse electrical conduction (forming a well-interconnected three-dimensional electrical conduction network), and varied porosity (forming a well-defined hierarchical porous structure) from these multiple constituents, the optimized quaternary nanocomposite electrode possesses a good combination of facilitated electron transport and enhanced ion diffusion and thus a twofold higher rate capability (capacitance retention: 83.3% vs. 28.9% at 80 A g−1 vs. 0.5 A g−1), twofold higher power density (84.1 kW kg−1 vs. 41.9 kW kg−1), and superior high-rate cycling stability (capacitance retention: 80.2% vs. 65.9% after charge/discharge at 10 A g−1 for 30,000 cycles) than its conventional activated carbon counterpart, while its high volumetric power density (50.5 kW L−1) strengthens its practical usefulness. Our research represents a novel approach to fabricate commercially available materials into practically useful ultrahigh-power supercapacitors at low cost, which may also be employed as a universal strategy to develop high-performance nanocomposites to benefit a wider range of application technologies. [ABSTRACT FROM AUTHOR]

The synergic combination of printed electronics and printed electrochemical sensors has recently emerged as a new route for developing smart chemical wearable devices applied to sweat monitoring. Sodium ion is one of electrolytes monitored in sweat to evaluate sweating level for electrolyte replacement recommendations. Herein, we report the development of new designed screen-printed electrodes, in which working electrode has been easily modified by drop-casting with the nanomaterial carbon black and a selective membrane cocktail, and the reference electrode with a polyvinyl butyral-based membrane. Once optimised all conditions, the screen-printed electrochemical sensor demonstrated no aqueous layer formation between working electrode and selective membrane, long-term potential stability, good shelf life, and resistance to interferences from oxygen and light. The carbon black-based sensor allowed for the detection of sodium ions in range 10-4 M e 1 M with a slope of 58 ± 3 mV/decade and a detection limit of 63 µM. The applicability for sweat analysis was evaluated by analysing three sweat samples collecting during running activity, obtaining concentrations of 44 ± 4 mM, 55 ± 6 mM, and 47 ± 3 mM, values in agreements with sodium ions content in healthy people, as well as using artificial sweat with recovery values of 90 ± 3%, 94 ± 2%, and 94 ± 5%. [ABSTRACT FROM AUTHOR]

The present work describes the performance of a new voltammetric sensor based on the modification of glassy carbon electrodes (GCE) with carbon black (CB) and botryosphaeran (BOT) (CB-BOT/GCE) for the electroanalytical determination of cyclobenzaprine. BOT is a fungal exocellular (1→3)(1→6)-β-ᴅ-glucan, which was used to improve the adherence of CB onto the surface of GCE. The electrochemical characterisation was performed by electrochemical impedance spectroscopy which showed an improvement in the transfer of electrons on the surface of the sensor developed in relation to the unmodified (bare) GCE. The voltammetric behaviour of cyclobenzaprine was studied using bare GCE, BOT/GCE, CB/GCE, and CB-BOT/GCE. All electrodes presented an oxidation peak (+ 1.0 V) for cyclobenzaprine, while the cyclobenzaprine peak intensity on CB-BOT/GCE was found to be 480% higher than the bare GCE. Through employing square-wave voltammetry, the analytical curve was found to be linear over the concentration range of 2.0 to 20.6 μmol L−1 (in 0.1 mol L−1 NaCl solution) with a detection limit (based on 3-sigma) of 0.63 μmol L−1. The developed electrochemical sensor exhibited excellent sensitivity and selectivity and was successfully applied for the voltammetric determination of cyclobenzaprine in pharmaceutical, biological, and environmental samples for the first time using the CB-BOT/GCE electrochemical sensing platform. [ABSTRACT FROM AUTHOR]

Lots of lithium ion battery (LIB) products contain lithium metal oxide LiNi 5 Co 2 Mn 3 O 2 (LNCM) as positive electrode active material. To increase the conductivity, conductive carbon-based materials including acetylene black and carbon black become necessarily consisted in electrodes. Recently, carbon nano-tube (CNT) appears as a popular choice for conductive carbon in LIB. However, a large quantity of the conductive carbon which cannot provide capacity as the active material will decrease the energy density of batteries. The ultra-high cost of CNT comparing to conventional carbon black is also a problem. In this work, we are going to introduce 'short length' and 'long length' carbon nano-tube (S-CNT and L-CNT) into electrode in order to design a reduced-amount conductive carbon electrode. The whole experiment will be done in 1 Ah commercial type pouch LIB. By decreasing conductive carbon as well as increasing the active material in positive electrode, the energy density of LNCM-based 1Ah pouch type LIBs with only 0.16% of L-CNT inside LNCM positive electrode could reach 224 Wh/kg and 549 Wh/L, in weight and volume energy density, respectively. Also, this high energy density LIB with L-CNT reveals stable cyclability may become a valuable progress in portable devices and electric vehicle (EV) applications. [ABSTRACT FROM AUTHOR]