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• Tunable oxygen reduction reaction properties is achieved by varying the electrolyte pH. • An A3B-type cobalt porphyrin-coated carbon black is designed as the catalyst. • Five electrolytes with pH values spanning from 0.7 to 13.7 are studied. • The composite exhibits the most positive potentials and the lowest Tafel slope at pH13.7. • Poor activity but high selectivity for 4-electron ORR is obtained at pH3.7. Understanding the pH-dependent mechanism of metalloporphyrin-based composite electrocatalystic oxygen reduction reactions (ORRs) can provide the basis for rational porphyrin molecular design. Tunable ORR properties of a cobalt porphyrin-based composite catalyst aFP-TCoP/C is accomplished by adjusting the electrolyte pH values spanning from 0.7 to 13.7. The composite performs the best ORR reactivity in the pH13.7 electrolyte, exhibiting the most positive characterized potentials (the ORR reduction potential E ORR of 0.76 V and the half-wave potential E 1/2 of 0.80 V) and the smallest Tafel slope of 43.1 mV dec−1. Whilst the sample with the pH3.7 electrolyte displays quite negative reduction potentials and a large Tafel slope, it exhibits an electron transfer number of 3.84, which indicates a nearly 4-electron transfer selectivity. The findings provide a practical protocol for regulating the catalytic reactivity and selectivity of ORRs by adjusting the components of electrolytes. [Display omitted] [ABSTRACT FROM AUTHOR]

Here, we report the investigation of carbon black as a cost-effective nanomodifier of thermoplastic polyurethane-based 3D printed electrodes for enhancing their electrochemical performances. The sensor was produced by scratching the working electrode with sandpaper, followed by the deposition of carbon black dispersion by drop casting. The morphological characterisation was carried out, showing the presence of a homogeneous coating of carbon black with a typical rough and spongy structure. Additionally, the electrochemical characterisation using electrochemical impedance spectroscopy highlighted the advantage of using carbon black as a nanomodifier of the working electrode surface after printing by obtaining the resistance of charge transfer equal to 327 ± 43 kΩ and 1.45 ± 0.06 kΩ for bare electrode and carbon black-modified electrode, respectively. When tested in cyclic voltammetry using ferro/ferricyanide, uric acid, dopamine, ascorbic acid, and free chlorine as target electroactive compounds, we demonstrated that the presence of carbon black cast onto the working electrode surface transformed the electrode from non-responsive to responsive electroanalytical tool. The analytical features of the developed responsive sensor were assessed for the detection of free chlorine in tap water with a linearity of 0.2–20 ppm and a limit of detection equal to 0.01 ppm. The accuracy was evaluated by spiking tap water samples with free chlorine concentrations equal to 0.5, 1, and 5 ppm, obtaining recovery percentages of (103 ± 2)%, (104 ± 3)%, and (95 ± 3)%, respectively. Additionally, the sustainability (electro)chemical-free pre-treatment thermoplastic polyurethane-based 3D printed electrodes modified with carbon black were evaluated by the White Analytical Chemistry principles. The advantages of 3D printed sensors modified with carbon black by drop casting were demonstrated, in terms of both the electrochemical performances and sustainable aspect, enlarging the use of carbon black as a nanomodifier to the 3D printed electrodes, beyond the 2D printed electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

• Cobalt phthalocyanine (CoPC) is dispersed on carbon black with different methods. • The dispersed materials are pyrolyzed under argon at various temperatures up to 900 °C. • CO faradaic efficiency remained > 45 % post-pyrolysis when catalyst loading > 7.9 wt%. • Spectroscopy (EXAFS) shows that the nature of the pyrolyzed material depends on CoPC loading. • Precursor crystallinity is a critical factor in the reactivity after pyrolysis. Understanding the structure-activity relationship of materials that are active for the CO 2 electrochemical reduction reaction (CO 2 ERR) is crucial for developing stable, high-performance catalysts. In this research, it is first shown that ball-milling is a highly efficient way to disperse cobalt phthalocyanine (CoPC) onto carbon black without influencing the CO 2 electroreduction performance of the resulting materials. Then, the link between the loadings of the CoPC precursor on the carbon support and the CO 2 ERR activity of the pyrolyzed materials is demonstrated. With CO current efficiencies higher than 45% and CO current densities as high as -20 mA cm−2 at -0.77 V vs. RHE, the materials with CoPC loadings of 7.9 wt% and higher were still surprisingly active after pyrolysis at 800 and 900 °C. On the other hand, the CO 2 ERR activity of the materials containing less than 6.1 wt% CoPC was drastically reduced after pyrolysis at these temperatures, with CO current efficiencies lower than 10 %. X-ray powder diffraction revealed that only the materials containing crystalline CoPC before pyrolysis showed good CO 2 ERR activity after pyrolysis at 800 and 900 °C. Furthermore, X-ray absorption spectroscopy showed that the loading of the CoPC precursor influenced the structure of the active sites in the pyrolyzed CoPC/C materials. Overall, this study highlights the importance of the dispersion of CoPC when forming a material that is catalytically active for CO 2 ERR after pyrolysis. [ABSTRACT FROM AUTHOR]

Modifying stainless steel (SS) surfaces with biocompatible materials is a practical approach to making SS an efficient electrode material for microbial electrochemical systems (MESs). However, a simple, cost-effective method to modify large-size SS is still missing. Here, we proposed to use spray coating to modify SS mesh (SSM) with acetylene black (AB) nanoparticles to make SSM an efficient anode material for MESs. The SEM images and Raman spectrum confirmed that AB nanoparticles could be uniformly coated onto the surface of SSM. The AB nanoparticles dramatically increased the specific surface area and biocompatibility of SSM. Consequently, when tested as the anode in MESs, the AB-coated SSM exhibited excellent biofilm formation ability, while the bare SSM saw inferior biofilm formation potential. Moreover, the current density achieved on the AB-coated SSM (1.95 ± 0.1 mA/cm2) was orders of magnitudes higher than that achieved on the bare SSM (0.01 ± 0.01 mA/cm2). Compared to other surface modification methods for SS, spray coating is simple, cost-effective, and most importantly readily for large-size SS electrodes. Therefore, spray coating of carbon nanoparticles holds excellent potential for scaling up SS electrodes for MESs. [Display omitted] [ABSTRACT FROM AUTHOR]

• A Box-Behnken design for graphite anodes slurries optimization was presented to highlight the importance of the component's interactions to obtained higher performed anodes of lithium-ion batteries customization. • The carbon black content is the most significant effect in both materials which is reflected in higher capacities and coulombic efficiencies. • For the overall behavior, the binder/carbon black interactions are relevant in terms not only of electrochemical performance but also in the obtention of more homogeneous and better adhesion anodes. The technological application of lithium-ion batteries (LIB) grows constantly, making customization of the batteries a current necessity and sometimes a challenge. In this paper we described carbon-slurry optimization process for anodes of lithium-ion batteries customization by using a surface response statistical experiment with four response variables such specific discharge capacity, coulombic efficiency, anodes mass deviation, and capacity retention. We studied two commercial graphite active materials by characterizing the materials via Raman spectroscopy, SEM, and electrochemical techniques. We corroborate the graphite structure for both materials but with morphological differences such as shape and particle size. The binder composition seems to interfere with the active carbon materials capabilities while it generates better performance for one of them. Although the chemical structure of both materials was confirmed to be the same via Raman experiments, SEM images shows critical morphological differences that interferes with the final slurry thus, affecting the electrochemical performance of the anodes. Further studies are required to understand ECSA and its possible effect on the charge/discharge capacities of the anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

• New insights on the reaction mechanism of Cu 2 Se with carbon-modified separator. • Altering the reaction mechanism of Cu 2 Se from bulk diffusion to surface capacitive. • The Cu 2 Se with carbon-modified separator delivers 95 mAh g −1 over 5000 cycles. • A promising strategy for the practical application of Cu 2 Se in aluminum batteries. Transition metal selenides (TMSs) become one of the most promising cathode materials for rechargeable aluminum batteries (RABs) due to the advantages of high specific capacity, low cost, and simple preparation process. However, TMSs are soluble in the acidic chloroaluminate ionic liquid electrolyte during cycling, leading to undesirable electrochemical performance. Herein, rechargeable Al-Cu 2 Se batteries are fabricated with acetylene black modified separator (AB/GF/A) showing excellent electrochemical performance with capacity retention of 95 mAh g−1 after 5000 cycles at 0.5 A g−1 and 166.1 mAh g−1 at 1.0 A g−1. By combining electrochemical tests and ex situ spectroscopy and electronic microscope characterizations, it is revealed that the dissolved Cu and Se species adsorbed on the surface of AB/GF/A still remain electroactivity, which transforms the diffusion-controlled mechanism of Cu 2 Se to surface pseudocapacitance-controlled behavior, thus suppressing the shuttle effects and boosting the reaction kinetics. The in-depth understanding of the functionalized separator in energy storage mechanism of TMSs could provide reference for further progress of RABs in the future work. Adopting carbon-modified separator in rechargeable aluminum batteries suppresses shuttle effect and alters the reaction mechanism of Cu 2 Se from bulk diffusion to surface capacitive, enabling long cycling life and fast reaction kinetics. [Display omitted] [ABSTRACT FROM AUTHOR]

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]

Synthesis of affordable electrocatalysts with high efficiency at low cost is crucial for large-scale water splitting. Molybdenum carbide (Mo 2 C) has been suggested to be a promising alternative to noble metal based electrocatalysts for water splitting. In this paper, we fabricated a nanotextured coating of wrinkled Ni-doped Mo 2 C on carbon fiber paper (CFP) from Ni, Mo and carbon black (CB) via a molten salt method. Such a novel electrocatalyst, denoted as Ni-Mo 2 C CB /CFP, shows an overpotential of 121.4, 209.3 and 426.4 mV to achieve a current density of 10, 20 and 50 mA cm−2 respectively in acidic medium. The hydrogen evolution reaction (HER) performance of other as-prepared CFP based electrodes (bare CFP, Mo 2 C/CFP, Mo 2 C CB /CFP, Ni-Mo 2 C/CFP and NiC x /CFP) also tested. We found that the addition of carbon black and the doping of Ni could significantly improve the electrocatalytic performance of Mo 2 C/CFP in terms of overpotential, Tafel slope and exchange current density. This work demonstrates a facile and scalable route using molten salt method for the synthesis of high-performance electrocatalysts from non-precious compounds on carbon materials. Image 1 • Carbon fiber paper (CFP) was employed as a carbon source and substrate of Mo 2 C. • The addition of carbon black (CB) contributes to the refinement of Mo 2 C particles. • Ni-Mo 2 C/CFP composite was prepared from Ni, Mo, CFP and CB by a molten salt method. • The Ni-Mo 2 C/CFP electrocatalyst exhibits excellent catalytic performance for HER. [ABSTRACT FROM AUTHOR]

The objective of this work is to explore whether carbon materials, which are usually utilized as additives for improving the electronic conductivity of oxide-based oxygen evolution reaction (OER) catalysts, could be replaced by silver nanoparticles. We integrate La 0.75 Sr 0.25 Mn 0.5 Co 0.5 O 3−δ , a perovskite with a limited electronic conductivity, in electrode compositions with either carbon materials (pyrolytic carbon of the Sibunit family – Sibunit-152, furnace black – Vulcan XC-72R, and Acetylene black) or silver nanoparticles, and investigate their OER activity in 1 M NaOH solution. We apply the rotating ring-disk electrode (RRDE) technique to separate the OER currents from those originating from corrosion of the additives under anodic polarization. We conclude that certain carbon materials would be better suited for use as conductive additives for oxide-based OER catalysts than silver particles. [ABSTRACT FROM AUTHOR]

Flexible organic cathodes with 3,4,9,10-perylenetetracarboxylic diimide (PDI) as the active component, carbon black (CB) as the conductive agent and thermoplastic polyurethane (TPU) as the elastomeric matrix are obtained in this work via a solution-based phase inversion approach. In the resulting PDI/CB/TPU cathodes, the mass ratios of the three components manifest profound influences on their composition, flexibility, conductivity and lithium storage behavior. The integrated PDI/CB/TPU cathode with optimized ratio can deliver impressive rate capability and good cycling stability in lithium ion batteries (LIBs). More importantly, the full LIBs with PDI/CB/TPU cathode and carbon cloth anode exhibit excellent electrochemical performances, which show no decay even at bending states, demonstrating the appealing prospects of the solution-processed organic cathodes in wearable secondary batteries. Obtained from a solution-based phase inversion approach, the flexible PDI/CB/TPU cathodes manifest excellent electrochemical performances and good mechanical stability in lithium ion batteries. Image 1 [ABSTRACT FROM AUTHOR]

Template-free synthesis of pure and Co-doped ZrO 2 tetragonal structured nanoparticles was achieved by the hydrothermal method and their photocatalytic, photoelectrocatalytic, and electrochemical energy storage supercapacitive properties were investigated for the first time. XRD revealed tetragonal crystal structure, while BET surface analysis suggested that Co-doped ZrO 2 has higher surface area (186.4 m2g−1) than that of the undoped sample (99.5 m2g−1). The band gap value was reduced from 4.95 to 2.12 eV due to incorporation of cobalt. Under visible-light illumination, photocatalytic and photoelectrocatalytic activities for methyl orange (MO) dye degradation were evaluated. The working electrodes have been prepared with 85 wt% active material (pure and doped ZrO 2), 10 wt% active carbon black, and 5 wt% polyvinylidene difluoride (PVDF) in order to perform the supercapacitive properties. The Co-doped ZrO 2 material exhibited 93.7% and 27.4% MO dye degradation within 100 min with the highest specific capacitance value of 2151.2 Fg-1. Image 1 [ABSTRACT FROM AUTHOR]

The need to deliver high performant and miniaturised electrochemical sensors has boosted the use of carbon nanomaterials as smart modifiers of working electrode surface. Among the carbon nanomaterials, the common and cost-effective carbon black has recently attracted the attention from the scientific community for its outstanding features as electrode nanomodifier for analyte detection. Herein, we report the structural and morphological characterisation of several types of carbon blacks, namely HP 160, HS20, MTN 990, N115, N220, N375, N660, PL6, Super P, and XE2B, by means of Raman spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses. Furthermore, the electrochemical characterisation of screen-printed electrodes modified with these carbon blacks was carried out by cyclic voltammetry and electrochemical impedance spectroscopy with ferro/ferricyanide as redox probe, highlighting the advantage to use carbon black as nanomodifier in respect to the bare electrode. Among several tested carbon black types, the lowest peak-to-peak separation and resistance to electron transfer values were achieved using screen-printed electrodes modified with CB N115, N375, HP 160 and PL6. The electrodes modified with these types of CB were successively tested in cyclic voltammetry towards epinephrine, benzoquinone, ascorbic acid, cysteine, catechol, and caffeic acid, observing a remarkable improvement of electrochemical performances in respect to the bare electrode, even when the amperometric mode was used. The results obtained demonstrated that several types of CB can remarkably improve the electrochemical performances of the sensors in terms of the decrease of applied potential or peak-to-peak separation, the improvement of the peak intensity, and the decrease of the resistance of the electron transfer due to several key features, including nanodimensions, the onion-like carbon structure, and the high number of defect sites. Image 1 [ABSTRACT FROM AUTHOR]

Biowaste, derived from cooking-oven-produced carbon nanoparticles (WCP), are incorporated into polyaniline (PANI) via in-situ chemical oxidative polymerization to achieve excellent electrochemical properties for application in supercapacitors. The WCP-PANI composite electrodes have shown high-performance charge storage, due to combinatorial effect of electrical double layer capacitance from WCP and pseudocapacitance from PANI. With increase in the WCP percolation, work function of PANI is increased, which improves the charge-trapping capabilities of composites. For such distinct charge-trapping mechanism, areal capacitance of the composite microelectrode remains near-constant with increase in scan rate or current density. This indicates the suppression of diffusion limitations at higher scan rates to considerably enhance the rate capability. Also, with increasing polymerization time, strong interaction in this conjugated system greatly improves the charge-transfer reaction between PANI and WCP. The areal capacitance of the composite electrode is found to increase more than 600 times over pure PANI electrode. Moreover, energy-power performance of the microelectrode reveals almost 550% increment in the power density with a mere 1% decrement in energy density. Such rationally synthesized WCP-PANI composite electrodes using biowaste carbon nanomaterials, provide opportunities for the development of next-generation green-supercapacitors with improved energy storage performance. Image 1 • Low cost sustainable economy: "reduce, reuse and recycle" of waste carbons are main three building factors for this report. • A novel charge-trapping phenomenon of PANI-WCP: diffusion limitation at higher scan-rate/current-densities is suppressed. • An unusual increment in areal capacitance : the reason of which is explained for the first time by a physico-chemical model. • Huge increment of energy power efficiency: almost 550% increase in power density with a mere 1% decrease in energy density. [ABSTRACT FROM AUTHOR]

The utilization efficiency of platinum (Pt) in polymer electrolyte membrane fuel cells (PEMFCs) needs to be increased to lower the cost of PEMFCs to facilitate their widespread commercialization. Here we developed a novel method to improve the Pt utilization efficiency by coating of polybenzimidazole (PBI) on the surface of the carbon support material; Vulcan. Electrochemical experiments revealed that Pt nanoparticle-loaded PBI-coated Vulcan (denoted as Vulcan/PBI/Pt) electrode possessed a much larger electrochemically active surface area (ECSA) compared with that of Pt nanoparticles directly deposited on Vulcan (Vulcan/Pt). The power density of the cell with Vulcan/PBI/Pt was 1.16 kW g−1, which was ca. 20% higher than that of the control cell using Vulcan/Pt (0.97 kW g−1). We considered that the higher Pt utilization efficiency of Vulcan/PBI/Pt than Vulcan/Pt resulted in such an enhanced ECSA and power density of the PBI-coated system. Two possible reasons were considered for the improvement; namely 1) the polymer layer prevented the loading of Pt nanoparticles into inaccessible micropores of Vulcan and 2) the polymer layer improved the coating homogeneity of Nafion ionomer, and thus improved the proton accessibility for Pt nanoparticles. Image 1 [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 Nano-conductive additives in composite electrodes play a significant role in influencing the electrochemical performance of the carbon anode in Li-ion batteries. These additives with a high electronic conductivity lead to the formation of a uniform solid-electrolyte interfacial layer, improved cycle life, and rate capability. In this work, the parameters that lead to such a performance improvement, namely the kinetic and transport properties, are carefully studied with carbon black (CB), carbon nanotubes (CNT) and a mixture of the two as conductive additives in mesocarbon microbeads (MCMB) anode. Experimental measurements indicate that the electrochemical reaction rate is controlled by interfacial kinetics up to moderately high C-rate (<6C). Though nano-additives do not affect the solid phase diffusivity, the diffusion of Li-ion is considerably influenced by stages and their coexistence that is revealed through X-ray diffraction of cells at different depths of discharge. Using electrochemical impedance spectroscopy of half-cells cycled at different temperatures, the activation energy for charge transfer reaction and activation energy for SEI layer diffusion are estimated. The results exhibit an improvement in electron transfer and an ionically conducting SEI layer with the use of a mixture of CB and CNT as conductive additives. It is expected that the estimated kinetic and transport parameters and their temperature dependence for the additives under consideration will be of tremendous utility in the thermal, electrochemical, or aging modeling of batteries employing MCMB as anode material. [ABSTRACT FROM AUTHOR]

Abstract Electrocatalysts with high activity toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential and desired for metal-air batteries, fuel cells, water-splitting and CO 2 reduction. Here, a series of Co-Co x O/N-doped Carbon (NC) is developed as bifunctional electrocatalysts via the pyrolysis of a simple physical mixture of cobalt-based metal-organic framework (MOF) and carbon black (CB). The obtained electrocatalysts exhibit considerably enhanced bifunctional activity as compared to the pure MOF derived counterpart. The essential roles of added CB in boosting the bifunctional activity are investigated. With the addition of CB, the surface concentrations of active pyridinic-N and graphitic-N for ORR and the surface CoIII/CoII ratios for OER are increased. Furthermore, the charge transfer efficiency and the electrochemically active surface areas (ECSAs) are also enhanced for the resulting electrocatalyst. The optimized Co-CoO-Co 3 O 4 /NC exhibits excellent bifunctional activity and durability, surpassing the commercial 20 wt% Pt/C (for ORR) and IrO 2 (for OER). When applied in an air electrode, the corresponding Zn-air battery with Co-CoO-Co 3 O 4 /NC presents the better performance than that with 20 wt% Pt/C. [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]

Aromatic Tb(III) chelates can be detected down to subnanomolar concentrations at polystyrene-carbon black composite electrodes on the basis of hot electron-induced electrochemiluminescence, and used as electrochemiluminescent labels in bioaffinity assays. The excitation mechanism is based on chemiluminescent reactions that are initiated by the field emission/tunnel emission of hot electrons from the composite electrode. The composition and the properties of the novel composite electrodes were studied in detail. Hot electron-induced electrochemiluminescence intensities obtainable with the present composite electrodes are comparable to the previously used metal/insulator-type electrodes without exhibiting considerable long-lived solid state electroluminescence background emission, unlike e.g. oxide-coated silicon and aluminum electrodes. C-reactive protein was finally determined in a heterogeneous sandwich-assay by using the present composite electrodes as a solid support material for the capture antibodies. The detection antibody was labeled with a commercially available Tb(II) chelate. Calibration curve for the determination of C-reactive protein was linear over two orders of magnitude and the detection limit was well below the clinical reference value, approx. 1 μg l −1 . Disposable polystyrene-carbon black composite electrodes are superior alternatives for e.g. silicon-based electrodes due to the low cost, easier manufacturing process and a very good performance e.g. in immunoassays. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive analysis of the impact of carbon nanotubes (CNT) and carbon nanofibers (CNF) composition on the performance of nano-Si anodes in lithium-ion batteries. The nano-Si anode suffers from chemo-mechanical issues caused by its large volumetric change (e.g., 280%) during cycling. One of the promising solutions in electrode level is to establish a robust electronic conduction pathway in Si anodes by incorporating CNT and CNF with high aspect ratios. The objective of this work is to quantitatively measure the performance improvement achieved by CNT and CNF based on their compositions and analyze the improvement mechanism through electrochemical methods. The results indicate that substituting a portion of carbon black with CNT and CNF in a range of 1 – 10 wt% can enhance the capacity retention (from 44% to around 60%) and the fast-charging and fast-discharging capabilities. Electrochemical impedance spectroscopy (EIS) and distribution of relaxation times (DRT) analyses revealed that 5% – 10% CNT and CNF conductors effectively suppressed contact impedances growths in Si anodes. In summary, our findings highlight the importance of precise control over the composition of CNT and CNF to achieve good electrode morphology and electrochemical properties for nano-Si anodes. [ABSTRACT FROM AUTHOR]

An acid-pasting approach is developed in this work to prepare the composites of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and carbon black (CB) by mixing both components in concentrated sulfuric acid. Different from the traditional powder processing, the solution-based fabrication strategy easily renders the effective combination of PTCDA and CB in the resultant CB/PTCDA composites, thus greatly improving their electrochemical performances. As the results, the composite with 20 wt% PTCDA shows excellent rate performances as the cathode material for both lithium ion battery (88 mAh g −1 at 5000 mA g −1 ) and sodium ion battery (100 mAh g −1 at 1000 mA g −1 ). As a facile and efficient processing strategy, the acid-pasting approach is expected to have wide application in the fabrication of organic electrodes in secondary batteries. [ABSTRACT FROM AUTHOR]

The effect of air pressure on electro-Fenton (PrEF process) was evaluated using two organic substances (maleic acid and Acid Orange 7) as model organic pollutants. First experiments were performed using a conventional carbon felt (CF) cathode. At room pressure, a slow removal of maleic acid was obtained, together with the generation of formic acid. Conversely, using pressurized air, the removal of maleic acid was dramatically accelerated and the formation of formic acid was not detected. The utilization of a carbon felt modified by the deposition of carbon black + PTFE mixture (MCF) and of pressurized air allowed to achieve even faster and almost total (>95%) removal of total organic carbon (TOC). Interestingly, the abatement resulted higher than the one obtained previously by direct anodic oxidation at boron doped diamond under comparable conditions. Similarly, in the case of Acid Orange 7 (AO7) the removal of the TOC increased with the pressure using both CF and the MCF. In particular, high removal of TOC (close to 80%) was obtained using the MCF at high current density (100 mA cm −2 ) under pressurized air. [ABSTRACT FROM AUTHOR]

Aqueous processing of lithium nickel manganese cobalt oxide (LiNi 0.5 Mn 0.3 Co 0.2 O 2 , NMC 532) cathodes was investigated by incorporating carbon nanotubes (CNTs) as the conductive additive. Morphology observation showed CNTs evenly disperse across the electrode, uniformly covering each primary particle, and form three-dimensional electronic pathways. A resistance measurement indicated the CNTs can improve the electronic conductivity of the composite electrode by an order of magnitude compared to carbon black. CNTs based electrodes showed higher rate performance, lower hysteresis, and better cycling performance with 99.4% capacity retention after 200 cycles in full pouch cells compared to 94.6% for carbon black based electrode. Meanwhile, the content of active materials in the electrode was increased from 90 wt% to 96 wt% and the energy density was increased by 11.7%. This research demonstrates an effective combined approach for achieving aqueous processed cathodes with enhanced durability while simultaneously achieving higher energy density by reducing the content of inactive components. [ABSTRACT FROM AUTHOR]

Hot electron-induced electrochemiluminescence (HECL) of calcein and calcein-Tb(III) complex was generated at oxide-covered aluminum electrode during cathodic pulse polarization. The excitation of calcein as a molecule or as a ligand is based on subsequent one-electron oxidation and reduction steps by oxidizing radicals and solvated electrons. During HECL excitation of calcein-Tb(III) solution a reaction product of the calcein is formed that also enables the photoexcitation of Tb(III) via the formed ligand derivative by ligand-sensitized mechanism. The determination of low concentrations of calcein with aluminum electrodes was complicated by a relatively strong background electroluminescence originating from the Al 2 O 3 -layer. Polyvinyl butyral-carbon black composite electrodes coated on brass were fabricated to solve this problem and a fifty-fold lower background emission was obtained for these novel composite electrodes in comparison to that of oxide-covered 99.9% pure aluminum electrodes. The obtained detection limits were 3.2·10 −10  M for calcein and 6.4·10 −9  M for calcein-Tb(III) at the present composite electrodes. These species could potentially be utilized as electrochemiluminescent labels in bioaffinity assays. [ABSTRACT FROM AUTHOR]

The modification of the surface of Ag nanoparticles supported on carbon black (Ag/C) with a small amount of Pd and the electrooxidation of allyl alcohol on the Pd-modified Ag/C (Pd/Ag/C) catalysts are investigated. The Pd/Ag/C catalysts with Pd/Ag atomic ratios of 0.45–1.48:100 are prepared by electrochemically depositing Pd on Ag/C. Structural characterization by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy, and electrochemical analysis reveal low loadings and small surface areas of the deposited Pd. The Pd/Ag/C catalysts are superior to Pd/C in activity for the electrooxidation of allyl alcohol in alkaline solution. When evaluated in terms of the glassy carbon substrate, Pd/Ag/C shows more negative onset and peak potentials and higher peak intensities than Pd/C, although Pd/C has a relatively high activity and the Pd loadings of Pd/Ag/C are much lower than that of Pd/C. When evaluated in terms of the electrochemically active surface area of Pd or the Pd loading mass, Pd/Ag/C has great advantages over Pd/C in activity. For instance, the Pd-mass activity of Pd/Ag/C is up to nearly 200 times that of Pd/C. Low cost is another striking advantage of the Pd/Ag/C catalysts. For ethanol oxidation, on the other hand, the Pd/Ag/C catalysts have no activity, while Pd/C has a relatively high activity. [ABSTRACT FROM AUTHOR]

In this work, a facial in-situ polymerization strategy is developed for the first time to fabricate the composites of polyimide and carbon black (PI/CBs) by the condensation of 1,2,4,5-benzenetetracarboxylic anhydride and p -phenylenediamine with the presence of carbon black. This composition method can effectively suppress the crystallization of PI and thus allows the sufficient contact of PI and carbon black. As the cathode material in LIBs, the PI/CB composite manifests an extraordinary capacity of 182 mAh g −1 at 0.1 A g −1 , close to the theoretical value of PI. Moreover, the capacity of the PI/CB composite can be retained as 116 m Ah g −1 even at an ultrahigh current density of 10 A g −1 , outperforming the recently reported polymer LIB cathodes. Under the same conditions, the mechanical mixture of highly crystallized PI sheets and carbon black shows a much poorer performance. The approach demonstrated herein is expected to be further applied as an effective processing method to build up high performance electrodes with organic species in secondary batteries. [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]

Electrochemical advanced oxidative processes (EAOPs) have been shown to be very efficient for the removal of organic pollutants that are not mineralized by conventional effluent treatments. These processes are based on the use of an electrocatalyst and/or photocatalyst for the in situ generation of hydrogen peroxide (H 2 O 2 ) and hydroxyl radicals ( OH), and these species are capable of mineralizing organic pollutants. This work aims evaluate electrocatalysts produced from ceria high aspect ratio nanostructures (CeO 2 HARN) supported on black carbon (Vulcan XC-72) in different mass proportions of CeO 2 HARN (1%, 2.5%, 4%, 5.5% and 10%) by examining the oxygen reduction reaction (ORR) in alkaline medium (1 mol L −1 NaOH) for the electrogeneration of H 2 O 2 . Vulcan XC-72 was used as a support because it has a high surface area, high catalytic activity and low cost. The CeO 2 HARN were prepared via a hydrothermal method and were supported on Vulcan XC-72 via an impregnation method. The CeO 2 HARN/C-based electrocatalysts were characterized physically by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and contact angle measurements and electrochemically by the rotating ring-disc electrode (RRDE) technique. The results of the electrochemical characterization of the materials indicated a considerable improvement in H 2 O 2 electrogeneration over that of pure Vulcan XC-72, and the electrocatalyst containing 1% CeO 2 HARN showed a lower starting potential and transferred 2.1 electrons in the ORR, therefore favoring the 2-electron mechanism and consequently providing a higher rate for H 2 O 2 electrogeneration, which was 95% compared with only 54% for pure Vulcan XC-72. These results show that the CeO 2 HARN/C-based electrocatalysts evaluated in this work are promising for in situ H 2 O 2 electrogeneration via EAOPs; in particular, the catalyst containing 1% CeO 2 HARN shows more promising results and contains a low metallic oxide load supported on the carbon, increasing its cost-benefit. [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]

Dye sensitized solar cells (DSSCs) have received significant attention due to their low production cost and easy fabrication process. However, the leakage and volatilization of the liquid organic solvent in the liquid electrolyte affect the long term stability of DSSCs. Therefore, in this present work, to improve the durability of DSSCs, polymethyl methaacrylate (PMMA) based polymer gel electrolyte (PGE) with different weight percent of carbon black (CB) was studied to replace the conventional liquid electrolyte. CB was used to improve the ionic conductivity of the PGE. DSSCs fabricated with the prepared PGEs exhibit very good long term stability in comparison to liquid electrolyte. The optimized DSSC with 0.57 weight percentage of CB in PMMA polymer matrix exhibits the highest photo-conversion efficiency of 5.52 ± 0.03% with short circuit current density (J sc ) value of 12.43 ± 0.04 mA cm −2 , open circuit voltage (V oc ) value of 766.02 ± 0.52 mV and fill factor (FF) value of 58.01 ± 0.02%. A significant enhancement of V oc is observed with the employment of the PGE. The impact of the PGE in the enhancement of V oc was studied by analyzing the charge transfer kinetics data at the interface of the photoanode and the PGE. Furthermore, the study of long term stability shows that after 1000 h of testing the optimized DSSC (PGE(0.57)) retains the J sc value at 83% of the initial performance exhibiting very significant long term stability in comparison to the DSSC fabricated with liquid electrolyte. [ABSTRACT FROM AUTHOR]

An effective tubular membrane cathode coated by heterogeneous Fe 2 O 3 nanoparticles with carbon black (CB), combined with oxygen evolution reaction (OER), was fabricated to simplify the operation of electro-Fenton system. It was demonstrated that the cathode had a favorable suitability for this system owing to the excellent performance presented on Field emission scanning electron microscopy (FE-SEM), Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and Cyclic voltammetry (CV). An optimal condition was obtained by response surface methodology (RSM) including pH of 6.7, current density of 13.0 A m −2 , membrane flux of 82.9 L m −2 h −1 , and CB/Fe of 6.2:1. Meanwhile, we achieved an estimated degradation efficiency of flutriafol (79.6%) in optimal condition without circulation of the influent. Effects of OER on the degradation of flutriafol via Ti/RuO 2 and Ti/SnO 2 -Sb tubular anodes were further interpreted by the gas production rate and the H 2 /O 2 value. High oxygen utilization of 78.8% was acquired when Ti/RuO 2 anode served as a sufficient oxygen provider. The electrocatalytic oxygen cycle, a key loop process, was firstly interpreted in this system, which achieved a great comprehensive electrocatalytic effect with the simplest operation and had a 74.5% removal of flutriafol in the verified experiment. [ABSTRACT FROM AUTHOR]

The hydrogen peroxide is a key and versatile compound that can be readily produced in one-pot electrochemical reactors via the 2 e − oxygen reduction reaction. In all the electrolyzers studied up to date, the external aeration is carried out by means of a compressor. In this work, the compressor is substituted by a device based on the Venturi effect to minimize the acquisition, maintenance and operating costs associated to the aeration of the reactor. Interestingly, it was found that this aerator can super saturate in oxygen the solution thanks to the formation of air bubbles. The catalytic effect of carbon black (CB) and/or polytetrafluoroethylene (PTFE) to increase the production of H 2 O 2 was studied, observing a synergistic effect when the CB/PTFE mixture was deposited on the carbon felt cathode. Efficient hydrogen peroxide generation was obtained at 15 mA cm −2 : instantaneous production rate of around 9.2 mg H 2 O 2 h −1 cm −2 and a corresponding current efficiency in the order of 90%. The limiting current density increased when the jet aerator was used thanks to i ) the super saturation of the solution (dissolved oxygen + air bubbles) and ii ) the ability of the CB/PTFE modified carbon felt to use them as oxygen source. The jet aerator is rather promising for the electrochemical generation of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

• Gold nanoparticle (AuNPs) functionalized ultra low-cost carbon black (CB) modified electrode was prepared. • Intrinsic Ni in the CB was utilized as a precursor for in-situ AunPs formation via alloy-like complex formation. • Highly efficient hydrazine-electrocatalytic oxidation was observed. • SECM technique was adopted for imaging of the surface-morphology. • Electroanalytical performance of the CB@AuNPs was explored. Gold nanoparticles (AuNPs) anchored carbon-nanomaterial chemically modified electrodes have been widely used for electrocatalytic applications. Indeed, only a fraction of AuNPs surface is found to be active, while most of the surface is inactive in nature. Thus, it is a challenging research to prepare active AuNPs suitable for electrocatalytic applications. Herein, we present a low-cost intrinsic nickel-containing carbon black (CB-Ni int , int= intrinsic nickel) modified glassy carbon electrode as an efficient matrix for forming highly active AuNPs (GCE/CB-Ni int @AuNPs). Specific electrocatalytic oxidation of hydrazine has been used as a model system to compare the active sites of the AuNPs. Various carbon nanomaterials like SWCNT, MWCNT, carbon nanofiber, and graphite nanopower-modified electrodes and externally deposited Ni (Ni ext) on the carbon-modified electrodes were examined as controls for the AuNPs formation and hydrazine electrocatalytic activity. Amongst all, the CB-Ni int matrix-modified electrode has shown the best electrocatalytic activity. The GCE/CB-Ni int @AuNPs was subjected to various physicochemical characterizations like FESEM, TEM, Raman, IR, XPS, and scanning electrochemical microscopy (SECM) using a Eu3+/2+ redox probe. Meanwhile, with Fe(CN) 6 3−, ex-situ derivatization of Ni ext as Ni-hexacyanoferrate, CB@Ni ext -HCF, was specifically inferred. It has been revealed that AuNPs form an intrinsic Au-Ni int alloy system on the interstitial position of CB-Ni int. On the other hand, a bulk layer-like AuNPs morphology was observed with the CB-Ni ext modified electrode case. This unique structural feature of the CB-Ni int @AuNPs sets a new trend in AuNPs-based chemically modified electrode preparation and electrochemical applications. As a proof of concept, selective electrochemical sensor application of hydrazine with a current sensitivity of 4.37 mA mM−1 cm−2, which is about 5-10 times higher than the majority of the conventional AuNPs-modified electrodes, without any common interference from H 2 O 2 , uric acid, ascorbic acid, dopamine, and cysteine, was demonstrated. [Display omitted] [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]

High-performance supercapacitors are widely studied, but few works have paid attention to the optimization of conductive bonding networks in the electrode to improve its electrochemical performance. Herein, a rationally designed three-dimensional (3D) conductive bonding network consisting of one-dimensional carboxylated carbon nanotubes (CNT-COOH) and two-dimensional reduced holey graphene oxide (rHGO) is introduced to porous carbon nanofiber/ultra-thin MnO 2 nanosheets (PCNF/U-MnO 2) electrode through vacuum filtration. The CNT-COOH/rHGO network endows the electrode with desired electron transport and ion diffusion properties for its advantages in 3D structures, conductivity and electrolyte wettability, which promote efficient use of PCNF/U-MnO 2 active materials. Thus, PCNF/U-MnO 2 in the electrode with CNT-COOH/rHGO network shows better capacitive performance than that of traditionally fabricated electrode with PTFE and acetylene black. Besides, CNT-COOH/rHGO network is conducive to structural stability of PCNF/U-MnO 2 electrode, and it obtains a capacitance retention of 87% even after 4500 cycles. Then, an asymmetric supercapacitor with PCNF/U-MnO 2 cathode and N, B-doped PCNFs anode has been assembled, which exhibits good flexibility using LiCl/PVA hydrogel as electrolyte and has a high energy density of 45 Wh kg−1 at a power density of 540.8 W kg−1. The strategy of CNT-COOH/rHGO network construction can be an effective and promising way beneficial to high-performance supercapacitor fabrication. [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]

Although lithium-sulfur batteries (LSBs) have rather high capacity and specific energy, they are facing many drawbacks, e.g. low electrical conductivity of sulfur (S 8 ) and lithium sulfide (Li 2 S), low capacity retention, large volume expansion of lithium sulfide in full lithiation state and dissolution of intermediate lithium polysulfides into the electrolytes. In order to address some drawbacks of the LSBs, here, sulfur was encapsulated by carbon black nanospheres (CN) and oxidized carbon nanosheet (OCN) with a sheet-like morphology by a mechanofusion and a colloidal coating techniques, respectively. Core-double shell S@CN@OCN composites were used as the cathode materials for Li-S batteries. The first CN shell can reduce the volume expansion of the sulfur during the charging process and also enhance the electrical conductivity. The second OCN shell can accommodate the volume expansion of the sulfur and decrease the “redox shuttle effect”. The LSB using the core-double shell S@CN@OCN cathode can provide the first and second discharge specific capacities of 1,313 and 1,279 mAh g −1 at 0.1C, respectively. In addition, the stability of this LIB tested at 1C over 400 cycles provides 77% capacity retention and 98% coulombic efficiency. This newly designed core-double shell S@CN@OCN structure may be the promising cathode of LSBs leading to the practical applications. [ABSTRACT FROM AUTHOR]

Various luminophores produce strong electrogenerated chemiluminescence during cathodic pulse polarization of the present insulating film-covered carbon paste electrodes in fully aqueous solutions. First electrodes made of a commercial conductive carbon paste were successfully utilized as working electrodes and their surface was characterized by ESCA. Then custom in-laboratory made improved composite electrodes were manufactured from the same insulating polymer and conducting carbon black particles. The relationship between the amount of carbon present on the composite electrode, in the bulk and on the surface, and the intensity of electrogenerated chemiluminescence was studied further. The overall performance of these composite electrodes makes them viable low-cost replacements for metal/insulator type electrodes such as oxide-coated silicon electrodes. [ABSTRACT FROM AUTHOR]

A new pyrolysis-pickling method was developed to prepare various lead oxide (PbO)/carbon black (CB) composites as the additives in the negative plates of lead-acid batteries to improve their high-rate partial-state-of-charge (HRPSoC) performance. Compared with CB, the PbO/CB composites prepared by the pyrolysis-pickling method have higher content of alkaline surface functional groups ( C alkaline ) and less content of carboxyl surface functional groups ( C COOH ) on CB particles which are still covered with small amount of PbO, meanwhile they have smaller BET surface area, but larger pore volume and average pore width. The hydrogen evolution process in the negative plates containing the PbO/CB composites is inhibited effectively due to the increased C alkaline on CB, while the redox processes (Pb ↔ PbSO 4 ) in these negative plates are accelerated obviously owing to the changes in their microstructure. The PbO/CB composites can impede the growth of PbSO 4 crystals and significantly increase the HRPSoC cycle life of the simulated test cells. In general, the PbO/CB composites with a lower PbO content may be the appropriate additives for the negative plate of lead-acid batteries. [ABSTRACT FROM AUTHOR]

Polyaniline (PANi) is an excellent electrode material with high pseudocapacitance for supercapacitors. Here the binder-free supercapacitor electrodes with high specific capacitance (458 F g −1 at 2 mV s −1 ) and Coulombic efficiency (100%) are successfully synthesized via a one-step potentialdynamic co-deposition of PANi and carbon black (CB). Significant synergistic effect between PANi and CB is demonstrated. Particularly, CB as the secondary dopant of PANi has been found to play an important role in producing higher conductivity, extended conformation structure, improved porosity, higher oxidation state and depressed hydrolysis effect, leading to superior capacitive performance. This promotes better understanding about synergistic effect between active materials and carbon additives, and opens up new research direction for high performance electrode design. [ABSTRACT FROM AUTHOR]

As significant as the electrolyte selection is for dual-ion battery applications, the characteristics of the graphitic cathode can also be decisive for the resultant cell operation. During this work, in order to find a promising electrode-electrolyte combination for Na-based dual-ion batteries, CCCV cycling tests were applied to different positive electrode compositions to optimize the effects of carbon black and binder as well as to mitigate the irreversible charge losses, by utilizing 0.5 M NaPF 6 /EC:EMC electrolyte which was found to be the most promising mixture in our preceding study. Electrodes consisting of 90 wt% KS6 graphite, 2 wt% carbon black and 8 wt% binder was found to be the most promising combination, and proved its superiority over SLP 30 type graphite, delivering 86.2 mAh/g discharge capacity by means of its lower particle size and larger surface area. Moreover, structural characterization tests of Raman spectroscopy and X-ray diffraction were implemented by providing qualitative and quantitative insights so as to elucidate and characterize the PF 6 − intercalation/de-intercalation characteristics for our Na-based dual-ion battery. The results of the tests acknowledged that the surface and the bulk of the electrode behave differently. [ABSTRACT FROM AUTHOR]

With the increasing needs of clean energy, supercapacitors, especially the activated carbon (AC) based supercapacitors are attracting great attentions for their theoretically infinite lifespan. However, they always age much faster than expected due to some mechanisms. In this work, we probed the ageing mechanism of AC based supercapacitors systematically by in-depth relevancy analyses of the main components in the supercapacitors after they have been aged at different temperatures for a rather long duration (1296 h) which was specially designed to simulate practical service limit of supercapacitors. On the one hand, XRD, TG-MS, XPS and BET analyses indicated that more than 23% of capacity decrease after high temperature ageing could be ascribed to the degradation of the crystal structure for the AC carbon, the agglomeration of the conductive carbon black, the collapse of the pore structure in the mixed AC layer and the separator, and the peeling off of the carbonaceous layer from the current collector, which was eroded as well during the ageing process. On the other hand, we found that the size of bare and solvated BF 4 − ions were about 2.86 Å and 11.11 Å, respectively, with the help of density functional theory (DFT) calculations. So the performance degradation of the supercapacitor could be ascribed to the lowered ion diffusing efficiency in the collapsed pores together with the increased electrical resistance of the whole system and the decreased specific area, which were resulted from all kinds of side-reactions ultimately. In addition, the relatively more serious ageing of the anode might be due to the more fluorochemicals and nitrogen compounds produced by side-reactions in the anodes. [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]

Electrochemical power sources, such as polymer electrolyte membrane fuel cells (PEMFCs), require the use of precious metal catalysts which are deposited as nanoparticles onto supports in order to minimize their mass loading and therefore cost. State-of-the-art/commercial supports are based on forms of carbon black. However, carbon supports present disadvantages including corrosion in the operating fuel cell environment and loss of catalyst activity. Here we review recent work examining the potential of different varieties of graphitic carbon nitride (gCN) as catalyst supports, highlighting their likely benefits, as well as the challenges associated with their implementation. The performance of gCN and hybrid gCN-carbon materials as PEMFC electrodes is discussed, as well as their potential for use in alkaline systems and water electrolyzers. We illustrate the discussion with examples taken from our own recent studies. [ABSTRACT FROM AUTHOR]

In this study Pt nanoparticles supported on NiO, MnO 2 , and on carbon black were prepared and tested for the ammonia electrooxidation reaction (AmER) in alkaline media. The morphology and structure of the catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), nitrogen physisorption, and their surface properties were studied using synchrotron radiation photoelectron spectroscopy (SRPES). Cyclic voltammetry, chronoamperometry and Tafel plots were used to study the electrochemical behavior of ammonia on Pt/metal oxide catalysts. Pt/NiO showed the highest current density and the lowest onset potential for AmER (-0.48 V vs. Hg/HgO) which increased in the order E onset (Pt/NiO) < E onset (Pt/MnO 2 ) < E onset (Pt/C). The reaction kinetic order with respect to the concentration of ammonia is close to zero, indicating fast surface adsorption of ammonia in agreement with previous studies on polycrystalline Pt electrodes, whereas the apparent Tafel slopes were found higher (56 − 69 mV dec −1 ) than previously reported values for Pt (39 mV dec −1 ). Our results show that the nature of the support strongly influences the size and electronic properties of the Pt nanoparticles, and as a result their electrocatalytic activity for AmER. [ABSTRACT FROM AUTHOR]