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A set of (Ti 0.2 Zr 0.2 Hf 0.2 Ta 0.2 Nb 0.2)C high-entropy carbide (HEC) ceramic samples were produced via spark plasma sintering (SPS) at a temperature of 1900 °C utilizing synthesized carbide powders. The carbide powders were synthesized via carbothermal reduction and derived from various carbon sources including carbon black, carbon microspheres, flake graphite, and graphitic carbon spheres. The impact of the different carbon sources was evaluated, for the first time, on the HEC's phase composition, microstructure, mechanical properties, and oxidation behavior. Results show that the HEC prepared using graphitic carbon spheres had a single-phase rock salt structure, with an average grain size of approximately 770 nm, which was smaller than that of HEC samples derived from the other carbon sources, due to its lower oxygen content, better dispersion, and higher chemical reactivity. Additionally, these HEC samples manufactured using graphitic carbon spheres exhibited 98.9% relative density, 20.39 GPa hardness, 4.5 ± 0.6 MPa·m1/2 fracture toughness, and excellent oxidation resistance. Therefore, by optimizing the reactivity and dispersion of carbon sources, high-performance HEC ceramics can be created. [ABSTRACT FROM AUTHOR]

The (W,Mo,Ta,Nb,Ti)(C,N) high-entropy carbonitride powders were synthesized by the carbothermal reduction nitridation method, utilizing equimolar proportions of either graphite or carbon black. The subsequent utilization of these pre-synthesized powders yielded carbonitride ceramics after spark plasma sintering. The choice of carbon source played an important role in the microstructure, phase compositions and mechanical properties. By employing carbon black with its fine particle size and high reactivity, the synthesized powder maintained finer size, narrow powder size distribution (350 ± 12 nm) and have less free-carbon (∼0.032 wt%), which contributed to the high hardness (26.8 ± 1.4 GPa) of the sintered ceramic. Conversely, utilizing graphite with its larger particle size and lower reactivity would increase the fraction of free-carbon, leading to the deterioration of the ceramic's performance. [ABSTRACT FROM AUTHOR]

SiBCN ceramics were prepared by a novel inorganic method: the in situ reaction of amorphous SiBON and C. Differences in the mechanical and ablation properties of composites prepared from flake graphite and carbon black (denoted as C f /CGZ and C f /CBZ, respectively) were compared to find a suitable carbon source. The results showed that flake graphite is the optimal carbon source. The fracture toughness of the C f /CGZ composite was 9.1 ± 0.4 MPa·m1/2, which is 23.0% higher than that of the C f /CBZ composite. This is because the flake graphite promoted crack deflection. Furthermore, after exposure to a plasma flame with a heat flux of 6.68 MW/m2 for 300 s, the mass and linear ablation rates of the C f /CGZ composite are 0.39 mg/s and − 0.19 µm/s, respectively, which is a decrease of 22.00% and 64.81%, respectively, as compared to those of the C f /CBZ composite. This is because of the directional distribution of flake graphite, which improved the thermal conductivity, reduced the ablation surface temperature, and facilitated the formation of a dense ZrO 2 /SiO 2 layer as an anti-ablation barrier. [ABSTRACT FROM AUTHOR]

Developers of direct carbon fuel cell (DCFC) technology seek to convert carbon to a pure or highly concentrated carbon dioxide stream that could ultimately be transported and sequestered. Carbon black produced by natural gas cracking processes is very pure and is therefore a candidate for use in DCFCs. In this study the performance of As received and Treated carbon blacks are compared in a planar cell configuration. At a more viable operating temperature of 750 °C, the As received carbon was found to produce a peak power density of 51 mW/cm2 at a current density of 104 mA/cm2. The performance then increased to 105 mW/cm2 at a current density of 145 mA/cm2 at 850 °C. Acid treatment of the carbon was found to improve performance of the DCFC at 750 °C by 35% (69 mW/cm2 at 160 mA/cm2) and only by 5% at 850 °C (111 mW/cm2 at 201 mA/cm2). • A commercial carbon black was used to fuel a planar, direct carbon fuel cell (DCFC). • An acid treatment method applied to the carbon black increased its wettability. • A DCFC output higher power density with Treated than with As received carbon black. [ABSTRACT FROM AUTHOR]

To characterize the nature of the interface between styrene-butadiene rubber (SBR) and carbon black (CB) in a filled rubber compound, we introduce an extraction protocol that uses toluene solvent in a high-pressure autoclave with sequential temperature steps of 90, 110, and 150 °C. This new approach removes unbound and physically bound (physisorbed) polymer from the CB-filled SBR compound to leave only chemically bound polymer which is 0.86% (0.0172 g polymer/g CB) and not zero as implied from extrapolating prior literature results. Rheological time sweeps on the unfilled gum SBR indicate that significant crosslinking can occur during annealing at 150 °C for this unsaturated polymer. This was the motivation for using the sequential extraction procedure versus direct extraction at 150 °C which gives a nearly six-fold higher amount of unextracted polymer due to such crosslinking. Analysis of the temperature dependence of bound rubber from 23 to 150 °C indicates that the physical interactions between the polymer and CB surface have a weaker component with a desorption energy (E d) of 6.8 kJ/mol and a stronger component with E d = 90.7 kJ/mol, the latter requiring an extraction temperature of 110 °C to remove the majority of it from the CB. [Display omitted] • New extraction method quantified chemically bound rubber as 0.0172 g SBR/g CB, corresponding to 31 chains per CB aggregate. • Weaker (6.8 kJ/mol) and stronger (90.7 kJ/mol) types of physical interactions between polymer and CB were distinguished. • Traditional evaluation of bound rubber at room temperature gives a convoluted measure of chemical and physical interactions. [ABSTRACT FROM AUTHOR]

Superior performance fillers are considered as an effective means to enhance the performance of carbon/graphite composites. However, poor interfacial properties and incomplete filler networks limit the performance enhancement of the composites. In this study, a new method was proposed to weaken this impact through the synergistic effect of the electrostatic self-assembly of nano carbon black (NCB) onto carbon nanotubes (CNTs). The results showed that the synergistic effect between NCB and the CNTs significantly improved the mechanical and electrical properties of the composites. NCB reduces the porosity of the composites and increases the interaction between the CNTs and matrix. The compressive strength of the composite was 143.2 Mpa, and the flexural strength was 46.3 MPa, which is 210% higher than that of the pristine carbon/graphite composites. Moreover, NCB and CNTs form a globally connected synergistic network in the carbon skeleton. Composites filled with CNTs/NCB exhibited the lowest resistivity and highest thermal conductivity, with a resistance that was 42% lower than that of pristine carbon/graphite composites at 44.8 μΩ m. All of these results suggest that the synergistic effect of CNTs/NCB show great potential to improve the performance of carbon/graphite composites. [Display omitted] • NCB was self-assembled with CNTs by electrostatic force, forming an enhanced phase with synergistic effect. • Targeted improvement of matrix properties near CNTs using NCB can enhance the interfacial properties. • Self-assembly of CNTs with NCB forms a synergistic network in the composite to enhance electrical and thermal properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • HCs with high mesoporous ratio of 58 % were synthesized from papermaking wastes. • HCs can be obtained from BL solid direct pyrolysis without the need for separation. • Chlorides derived from DS were used as pore-enlarging agents to make mesopores. • DSCl x improves electrochemical performance of the synthesized HC anodes efficiently. • This study presents an economical and eco-friendly method for recycling BL and DS. Porous hard carbon anodes, with large interlayer space and high adsorption ability, can offer much better cycle stability and higher discharge capacity for potassium-ion batteries compared to commercial graphite anodes. However, most commercial hard carbons are synthesized from relatively expensive high-molecular polymers. In this study, pulping and papermaking wastes were utilized as precursors for producing hard carbons and pore-enlarging agent, respectively. Specifically, after thorough mixing through ball milling, black liquor solids and deinking sludge were utilized to produce porous hard carbon anodes via co-pyrolysis. The results show that direct pyrolysis of black liquor can produce hard carbons efficiently, eliminating the need to extract lignin from black liquor. Moreover, it is shown that the pore-enlarging agent derived from deinking sludge can enlarge much portion of pores on hard carbons, resulting in abundant mesopores. Electrochemical tests demonstrate that the synthesized porous hard carbon anodes can achieve highest specific capacity of 303.5 mAh g−1 at 100 mA g−1 using a 1.0 M potassium hexafluorophosphate electrolyte in a mixture of diethyl carbonate and ethylene carbonate. Additionally, the synthesized porous hard carbon anodes exhibit low average capacity decay per cycle of 0.06 % at 100 mA g−1 when tested with a 1.0 M potassium bis(fluorosulfonyl)imide electrolyte in the same solvent mixture after 500 cycles. Therefore, recycling black liquor and deinking sludge to produce porous hard carbon anodes for potassium-ion batteries is a promising approach for environmental and energy sustainability. [ABSTRACT FROM AUTHOR]

Fabrication of ceramic materials containing high amount of porosity with controlled size and structure is a critical factor for various applications. In this study, porous alumina ceramics were prepared by addition of 5–30 vol% carbon black (CB) powders with different specific surface area (SSA) into the alumina matrix as a pore forming agent and application of partial sintering via spark plasma sintering (SPS) technique. After removal of CB particles from the ceramic structures, physical, mechanical, and thermal properties of the porous alumina ceramics were investigated. The open porosity level was detected between 38.48 and 59.81% depending on the type and amount of CB removed. The compressive strength of the sintered samples was measured as ∼150 MPa, which is ∼3 times higher than that of the conventionally sintered samples thanks to the strong neck formation between grains. The large pores formed by removal of CB agglomerates in case of using CB powders with SSA of 107 and 254 m2/g resulted in a change in thermal conduction mechanism from lattice vibration to thermal convection. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) can improve the efficiency of oxygen evolution reaction (OER). However, metal SACs anchored on carbon materials are relatively uncommon for the OER. In this paper, using carbon black as carrier, NiFe SACs are fabricated by one step pyrolysis method. When the weight ratio of Ni/Fe is lower than 5:3, NiFe@C exibits highly-dispersed SACs over carbon in addition to some Ni 3 Fe alloy. The prepared NiFe@C 5:3 SACs showed excellent OER performance with an overpotential of 322 mV and 438 mV for current density of 10 mA/cm2 and 100 mA/cm2, respectively. The Tafel slope of NiFe@C 5:3 was as small as 87.6 mV/dec, indicating fast charge transfer of NiFe@C 5:3 during OER process, which was also confirmed by electrochemical impedance spectra with R ct = 18.07 Ωcm2. Meanwhile, NiFe@C 5:3 had the highest specific capacitance of 5 mF/cm2 with good stability. This work provides a reference for designing electocatalyst material for efficient, stable and economical OER process. • NiFe SACs are fabricated by pyrolysis method. • NiFe@C 5:3 exibits highly dispersed SACs on carbon. • The required over potential of NiFe@C 5:3 for current density 10 mA/cm2 is only 322 mV. • This work provides a reference for designing electocatalyst material. [ABSTRACT FROM AUTHOR]

Surface mass loss rates due to sublimation and oxidation at temperatures of 3000–7000 K have been measured in a shock tube for graphite and carbon black (CB) particles. Diagnostics are presented for measuring surface mass loss rates by diffuse backlit illumination extinction imaging and thermal emission. The surface mass loss rate is found by regression fitting extinction and emission signals with an independent spherical primary particle assumption. Measured graphite sublimation and oxidation rates are reported to be an order of magnitude greater than CB sublimation and oxidation rates. It is speculated that the difference between CB and graphite surface mass loss rates is largely due to the primary particle assumption of the presented technique which misrepresents the effective surface area of an aggregate particle where primary particles overlap and shield inner particles. Measured sublimation rates are compared to sublimation models in the literature, and it is seen graphite shows fair agreement with the models while CB underestimates, likely a result of the particle shielding affect not being considered in the sublimation model. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanogold-loaded porous acetylene black (Au@PAB) as a conductive hybrid nanofiller. • Au@PAB incorporating carbon nanofiber networks (CNFs) was constructed. • The Au@PAB/CNFs-PE nanosensor was utilized for the ultrasensitive quantification of capmatinib (CMT). • The sensor exhibited good selectivity and repeatability. • We achieved excellent LOD, sensitivity, and a good recovery rate in human biological fluids. In the current study, the first voltammetric method is constructed for the ultrasensitive quantification of capmatinib (CMT), a targeted therapy drug falls within the category of tyrosine kinase inhibitors (TKIs), using a modified carbon nanofibers paste electrode (CNFs-PE). Nanogold-loaded porous acetylene black (Au@PAB) as a conductive hybrid nanofiller incorporating carbon nanofiber networks (CNFs) was synthesized. The surface morphology of the synthesized Au@PAB and the ternary nanocomposite Au@PAB/CNFs was elucidated using various analytical techniques. The results show Au@PAB hybrid nanofiller incorporated CNFs has a critical property that increases electrocatalytic performance. The impact of scan rate, pH, and supporting electrolyte on the electrocatalytic response of CMT was explored on the Au@PAB/CNFs-PE nanosensor. Under optimum adsorptive stripping square-wave voltammetric (AdS-SWV) conditions, the developed probe displayed good sensitivity, selectivity, and a remarkable wide linear dynamic range of 1.0 × 10-8 – 2.0 × 10-5 M of CMT. The low limits of detection (LOD) and quantification (LOQ) were 4.6 nM and 15.4 nM of CMT, respectively. The features of easy operation and good selectivity make this nanosensor a talented candidate for CMT detection in complex samples, as demonstrated by its application in spiked biological samples with good recoveries. [ABSTRACT FROM AUTHOR]

Micrometer long multilayer carbon nanoribbons with high oxygen content and nitrogen doping were obtained from the nitric acid treatment of Black Pearls 2000. The nanoribbons (NRs) exhibited yellow light emission under UV excitation. The oxidation of other grades of carbon black yielded irregular and small graphene oxide fragments or carbon quantum dots instead. Remarkably, the familiar and straightforward treatment of carbon materials with nitric acid reemerges as a powerful tool for the synthesis of technology-relevant carbon nanoribbons, and unlocking the potential of such straighforward oxidation chemistry applied to inexpensive and commercially available carbon black. [Display omitted] • Carbon nanoribbons are uniquely obtained from oxidation of carbon black (CB) BP2000. • Oxidation of Vulcan, Monarch and Acetylene Black grades yield graphene oxide sheets and carbon dots. • Nanostructure depends on CB surface area, amount of amorphous carbon and size of basic structural units. • Nanoribbons have yellow emission modulated by nitrogen doping and to oxygen defects. [ABSTRACT FROM AUTHOR]

In this work, different carbon sources, such as nano-sized carbon black (CB), carbon nanotubes (CNT), carbon fibers (CF) and graphene (GR), were reacted with titanium micro-powders, to synthesise titanium carbide (TiC) in the mixed molten salts of LiCl–KCl–KF at 1100 °C for 6 h. There experiments were performed to investigate the accuracy of "carbon-template-growth" mechanism for the formation of TiC, that was proposed previously using micro-sized titanium and submicro-sized CB powders. The products synthesised from the different carbon sources were observed and characterised by scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results showed that the visual morphologies of the TiC products mainly retained the shapes of the as-received carbon sources, that is, they presented an equiaxed-shape with a grain size of 10–20 nm from CB, a shell layer along the outer surface of the CNTs and CF, and a flake-shape with the GR. These morphologies reveal that the formation of TiC is indeed controlled by the "carbon-template-growth" mechanism. [ABSTRACT FROM AUTHOR]

• Re nanoparticles are prepared by a joint reduction method of carbon and hydrogen. • The as-obtained Re nanoparticles are only about 108.6 nm with a slight C and O. • The presence of carbon black can significantly reduce the particle size of products. • A further reduction of hydrogen can decrease the contents of C and O residues. Ultrafine powders are crucial for the preparation of high-performance Re-based materials via low-temperature sintering. In this work, a joint reduction method of carbon and hydrogen is proposed to prepare Re nanopowder for the first time. The former carbon black can significantly reduce the particle size of final products, and the latter hydrogen reduction can decrease the contents of carbon and oxygen residues. And the as-obtained rhenium nanopowder is only about 108.6 nm with a slight carbon (0.019 wt%) and oxygen (0.03 wt%). This method is straightforward, easy to implement, low-cost and conducive to the large-scale industrial production. [ABSTRACT FROM AUTHOR]

• This study describes the synthesis of N and F co-doped carbons by zeolite templating method using fluoropyridine. • N, F co-doped carbons showed better ORR activities than N doped carbon prepared using pyridine. • The optimized N, F co-doped carbon showed a quite high half-wave potential of 0.87 V vs. RHE. • Precise introduction of semi-ionic F species boosted the ORR activity. Heteroatom-doped carbons have attracted increasing attention in recent years as inexpensive high-performance electrocatalytic materials owing to their electrical properties. A precisely controlled synthesis method for heteroatom-doped carbons is important to improve their performance and expand their applications. In this study, we developed a fluoropyridine-medicated zeolite templating method for Nitrogen/Fluorine (N/F) co-doped carbons. The N/F co-doped carbons showed better catalytic performances for oxygen reduction reaction (ORR) than N-doped carbon prepared using pyridine. In particular, the optimized N/F co-doped carbon exhibited a higher half-wave potential (0.87 V vs. RHE) than commercial Pt-loaded carbon black and N/F co-doped carbons reported in the literature. The comparative studies using various N/F co-doped carbons revealed that semi-ionic bonded C-F might improve ORR activity. In contrast, the contribution from covalent or ionic C-F to improving ORR activity would be negligible. [ABSTRACT FROM AUTHOR]

MoO 3 is passionately examined as anode materials for lithium-ion batteries (LIBs), because of its exclusive interest due to high theoretical capacity (1117 mAhg−1). This article reports the synthesis of MoO 3 nanoparticles by a simple solution combustion method using tamarind seed powder as a novel fuel where it produces in situ excess carbon by which it can eliminate the addition of acetylene black during the preparation of electrodes for LIB as a conducting material. The prepared MoO 3 nanoparticles were characterized by XRD for structural analysis, vibrational bonding's through FTIR, CHN elemental analysis, BET for pore size distribution and specific surface area, morphology by SEM and TEM. Presence of carbon content in MoO 3 nanoparticles show an excellent electrochemical performance by showing initial discharge capacity of 1171 mAhg−1 and stabilized to 162 mAhg−1 after 200 cycles and Columbic efficiency close to 100%. [ABSTRACT FROM AUTHOR]

Developing effective earth aboundant non-precious metal electrocatalysts for oxygen reduction reaction (ORR) is highly demanded in clean energy conversion systems, such as fuel cells. In this work, we demonstrate N,F dual-doped carbon embedded with Co&CoN paragenetic structure (N,F–Co&CoN@C) as an effective ORR electrocatalyst through directly pyrolyzing the solid mixture of cobalt chloride hexahydrate, melamine hydrogen fluoride and carbon black in an N 2 atmosphere. N,F–Co&CoN@C prepared at 700 °C (N,F–Co&CoN@C700) exhibits an excellent electrocatalytic performance with the ORR peak potential (E p) at 0.875 V, the half wave potential (E 1/2) at 0.871 V and a nearly four-electron reaction path in 0.1 M KOH. It also displays a better stability and methanol-tolerance than that of the commercial 40 wt% Pt/C. Origin of this outstanding performance of the prepared N,F–Co&CoN@C700 comes from the synergistic effect of Co&CoN and N,F–C in the hybrid materials. TEM images, STEM-mapping images, XRD and XPS results verify that N,F–Co&CoN@C700 has a core@shell structure with Co&CoN paragenetic structure embedded in N, F dual-doped carbon. Its specific surface area is calculated to be 1018 m2/g with a high defect degree of the I D /I G at 1.31. Image 1 • N,F-doped carbon with Co&CoN paragenetic structure (N,F–Co&CoN@C) is prepared. • N,F–Co&CoN@C700 shows an E p at 0.875 V, E 1/2 at 0.871 V and a four-electron path. • N,F–Co&CoN@C700 has a better durability and methanol-tolerance than 40 wt% Pt/C. • N,F–Co&CoN@C700 owns the synergistic effect of Co&CoN and N,F–C in the hybrid. • Its specific surface area is 1018 m2/g with the I D /I G at 1.31. [ABSTRACT FROM AUTHOR]

We design and construct a novel heterostructured CoSe 2 /Ni 3 Se 4 @N-doped carbon nanosheets/Ketjen black carbon (denoted as CoSe 2 /Ni 3 Se 4 @NC/KB) via the combination of pyrolysis and hydrothermal method. As a result of the exceptional synergism between CoSe 2 and Ni 3 Se 4 as well as high conductivity of carbon materials, the obtained CoSe 2 /Ni 3 Se 4 @NC/KB drives an OER current density of 10 mA cm−2 by an overpotential of 260 mV and displays a low Tafel slope of 68 mV dec−1, outmanoeuvring commercial RuO 2 and IrO 2 , control groups (i.e. Ni 3 Se 4 @NC/KB, CoSe 2 @NC/KB, and CoSe 2 /Ni 3 Se 4 @NC), as well as most hybrids of selenides and carbon materials reported recently. • We design a novel heterostructured CoSe 2 /Ni 3 Se 4 @NC/KB hybrid. • This hybrid is constructed via the combination of pyrolysis and hydrothermal method. • This hybrid affords excellent OER activity, superior to commercial RuO 2 and IrO 2. • The marked comprehensive properties of this hybrid are due to its rational structure. [ABSTRACT FROM AUTHOR]

Carbon-metal hybrid materials have shown promising performance as electrocatalysts for CO 2 reduction. Here, a comparative study of how different carbons supports influence this reaction is presented. The tested carbon supports were graphene oxide, multi-walled carbon nanotubes, carbon black and activated carbon while the metal complex selected was copper(II) phthalocyanine (CuPc). The CuPc supported on carbon nanotubes (CNT) and carbon black were found to give higher faradaic efficiencies (FE) for reduced carbon products, i.e. 66.3% and 81.8%, respectively compared to graphene oxide (0.0%) and activated carbon (12.8%). Amongst various sizes of CNT, long and thin tubes (in the range of 10–30 nm diameter size, 10–30 μm length) demonstrated higher FE (66.3%) relative to shorter and thicker ones (7.4%). Additionally, the novel use of CNT synthesized from post-consumer plastic waste was also explored as a potential carbon support material. It demonstrated comparable performance to commercial CNT in terms of FE (70.4%). Image 1 • Carbon nanotubes (CNTs) and carbon black were found superior for CO 2 reduction. • Long (10–30 μm) and thin (10–30 nm Ø) CNTs provided better faradaic efficiency. • The plastic waste derived CNTs were successfully applied as carbon support. • Waste derived CNTs resulted in comparable faradaic efficiencies to commercial CNTs. [ABSTRACT FROM AUTHOR]

The quantification of surface groups is a key characterization for different carbon materials as their behavior in colloidal dispersion, their interaction with proteins, drugs or polymers as well as their aggregation behavior strongly depend on the type and number of surface groups. Some of the most challenging groups are those containing oxygen as the typical characterization methods do not allow for a highly sensitive and reproducible quantification of carboxylic, lactonic and alcoholic groups. The only known wet-chemical method that is able to yield quantitative results is the Boehm titration. However, this method is also known to be extremely demanding regarding procedure compliance, requires large amounts of sample, and leads to rather large standard deviations. Here we report on a significantly improved titration method for the quantification of oxygen containing surface groups. All methodical aspects like sample preparation, reaction time, filtration medium, volumetric and gravimetric methods have been optimized, leading to the detection of carboxylic, lactonic and alcoholic groups with a standard deviation of ±1 μmol/g while using only small amounts of sample material. The method has been successfully applied on a broad variety of hydrophilic and hydrophobic carbon materials including nanodiamond, partially graphitized nanodiamond, multiwall carbon nanotubes and acetylene black. Image 1 [ABSTRACT FROM AUTHOR]

• C@ZrSiO 4 pigment was prepared by molten-salt assisted method. • The pigment shows regular microcubes morphology with particle size of 3 μm. • The molten-salt increases the carbon content of the pigment, which possesses deep black hue (L* = 33.08). • The molten-salt assisted C@ZrSiO 4 pigment exhibits good dispersity and thermal stability. A core-shell structure zirconium silicate encapsulated carbon (C@ZrSiO 4) pigment was synthesized by a molten-salt assisted method. The experimental results indicated that the Na 2 WO 4 molten-salt associated with the synthesis of ZrSiO 4 at low temperature and controlled the morphology of the encapsulation pigment simultaneously. The encapsulated pigment prepared with the assistance of Na 2 WO 4 molten-salt showed regular microcubes about 3.0 μm, while the pigment in the absence of molten-salt have serious aggregation with a particle size of 12.78 μm. Moreover, the maximum addition amount of carbon black was increased significantly from 15 wt% to 40 wt% after adding molten-salt, while the chromatic value L * of C@ZrSiO 4 pigment decreased from 68.21 to 33.08 accordingly. The pigment exhibited excellent thermal stability at high temperature, making it a promising candidate for ceramic decoration. [ABSTRACT FROM AUTHOR]

A direct carbon fuel cell is an electricity generation device using solid carbon as a fuel directly with no reforming process. In this study, three-carbon fuels, graphitic carbon (GC), carbon black (CB), and biomass carbon (BC) are tested as the fuel to investigate the influence of carbon fuel properties on the cell performance in HDCFC with a traditional nickel oxide as the anode. Either an electrolyte-supported cell with a thin nickel oxide anode or an anode-supported cell with a thick nickel oxide anode is used to evaluate the electrochemical reactivity of carbon samples. These three-carbon fuels are characterised on the crystal structure, particle size, composition, and surface property. It is found that GC shows excellent cell performance on thin nickel oxide anode. However, it displays relatively slow electrochemical reactivity on the thick anode due to its great extent of carbon oxidation. BC shows good initial cell performance but fast degradation of the cell performance, as much more hydrogen is released at the beginning of the cell test. The anode reactions of HDCFCs are explored by the in-situ gas analysis in open circuits and under current load conditions. It is observed that GC produces the highest amount of CO among these three fuels, suggesting that carbon oxidation is the dominant electrochemical process in HDCFCs after a certain time when most of the hydrogen is released from the pyrolysis process. Graphite carbon (GC) shows excellent durability performance at 0.7 V load in an electrolyte-supported HDCFC with CO as the primary gas in the outlet. Image 1 • Graphite oxidation is investigated in a NiO-based HDCFC. • Graphite shows the best cell performance on the electrolyte-supported HDCFC. • Cell performance is dependent on both of the fuel property and the cell configuration. • In-situ gas analysis is an effective way of identifying possible electrochemical reactions. • CO is the main gas for graphite oxidation. [ABSTRACT FROM AUTHOR]

N-doped carbons (NCs) have attracted considerable attention for their outstanding physicochemical properties, including tunable porosity, electronic features and modified surface. Here, we report the preparation of hierarchically porous NCs derived from the direct pyrolysis of ZIFs (ZIF-7 and ZIF-8) and poly– m –phenylenediamine-covered carbon black (P m PDA-C) for the stabilization of Cu nanoparticles (NPs). The configuration of N species can be effectively regulated by changing the ligand of ZIFs and pyrolysis atmosphere. A remarkable N configuration synergistic effect is observed in the oxy-carbonylation of methanol to dimethyl carbonate with molecular oxygen. The results indicate that the Cu NPs on pristine carbon have a turn over frequency (TOF) of 4.4 h−1 for the reaction, while those on NCs from ZIF-8 and ZIF-7 present TOF values as high as 17.9 h−1 and 28.5 h−1, respectively. The extensive characterizations reveal that NCs with a nitrogen content of 2–5 wt% and a pyrrolic-/pyridinic-N molar ratio of 2–3 are vital for the performance enhancement of Cu NPs. This work shows that the stabilization and enhanced performance of active Cu NPs on NCs are realized by the rational design of precursors to generate the proper N configurations. Image 1 • A series of NCs are prepared from ZIFs with N content in the range of 0–20 wt%. • The N configuration is regulated by ligand of ZIFs and varying pyrolysis conditions. • The performance of supported Cu catalysts is correlated with N configurations. • NCs with 2–5 wt% N and pyrrolic-/pyridinic-N ratio at 2–3 are vital for Cu catalysis. [ABSTRACT FROM AUTHOR]

A high oxidation stability of electrode components, especially of conductive carbon additives, is of importance in order to realize high-voltage (5 V-class) Li-ion batteries with higher energy densities. In this work, the oxidation stability of acetylene blacks is studied by analyzing the capacity (i.e. , quantity of electricity) arising from their oxidation reactions via chronopotentiometry up to 5.5 V (vs. Li+/Li) in a highly concentrated electrolyte with high oxidation stability. Annealing at 1200 °C can improve their oxidation stability below 4.8 V by reducing the amounts of surface active sites. However, further raising the annealing temperature significantly degrades the stability at higher potentials (>4.8 V) due to the electrochemical anion intercalation induced by progressive graphitization. This work suggests that, for 5 V-class batteries, conductive carbon additives should be optimized to simultaneously minimize surface active sites and excessive graphitization. Image 1 [ABSTRACT FROM AUTHOR]

A hierarchical porous carbon (HPC) structure was developed from the waste orange peel using KOH as an activating agent. In HPC, the carbon has interconnected hierarchical pores size of which lies between 2 nm and 5 μm. HPC/S composite was prepared by melt-diffusion method and analysed for electrochemical performance. HPC/S exhibits a high initial discharge capacity of 870 mAhg−1 at 0.2C and 734 mAhg−1 at 0.4C. The Carbon-black (CB)/Sulfur (S) composite was also prepared and characterized. A comparative study was done with the CB/S composite, which shows poor cyclability and a discharge capacity of 332 mAhg−1 at 0.2C rate considering 1C = 1672 mAhg−1. Sulfur confinement in the HPC structure leads to superior electrochemical performance of the HPC/S composite ensuring a promising cathode material. [Display omitted] • Hierarchical porous carbon (HPC) structure is synthesized by using KOH as an activating agent. • HPC/S composite is prepared by adopting the melt diffusion method. • HPC/S retains 25.5 % more sulfur, addressed as pore-confined sulfur. • Comparative study shows superior electrochemical performance of HPC/S than CB/S composite. [ABSTRACT FROM AUTHOR]

• Fluorescent chiral carbon microspheres (FCCMSs) and carbon nanodots (CNDs) synthesized together by hydrothermal method. • Chiral, thermal, and electrical properties shown promising for commercial applications of FCCMSs. • Larger quantum yields (QYs) obtained for D-ascorbic acid (AA) derived CNDs than for L-AA ones and for higher temperature and longer reaction time. • A lower temperature or a shorter reaction time considered useful to tune blue to green emission ratio of D-AA CNDs. Fluorescent carbon microspheres (CMSs) and carbon nanodots (CNDs) synthesized together in one pot have received much attention in the past decade. Here we report the use of L- and D-ascorbic acids (AA) to prepare CMSs with different chirality and CNDs with different fluorescent emission by the hydrothermal method. The CMSs emit a blue light while the CNDs emit a green one under 365 nm UV light. The reaction conversions of CMSs prepared with this method are over 25% when the reaction temperature is above 180°C. Circular dichroism, specific rotation, and photoluminescence of CMSs were measured. The analyses show that the L- and D-AA-based CMSs exhibit different chiral spectra. The graphene-like structures of CMSs are revealed by Raman spectroscopy. A possible formation mechanism of the CMSs and CNSs is proposed. In addition, the CMSs after calcination were found to achieve higher electrical and thermal conductivities comparable to those of the commercial carbon black. Photoluminescence analyses of CNDs show that the relative fluctuation between the blue and green emissions determines the shifting of blue and green hybrid color of the synthesized CNDs. D-AA derived CNDs show a higher quantum yield (QY) close to 1% and a stronger green emission. The blue-emitting CNDs and the green-emitting ones could be separated with the larger green CNDs kept inside the dialysis tube. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, polycrystalline platinum-based nanoparticles were deposited onto two different carbon supports: carbon black and multiwalled carbon nanotubes. The samples were characterized by Raman spectroscopy, transmission electron microscopy and tested using a Kelvin probe to measure the work function changes upon oxygen adsorption at different temperatures. The same materials were evaluated as electrocatalysts for the oxygen reduction reactivity under acid conditions, in a three-electrode configuration, in a rotating disc electrode setup. Since both Kelvin probe work function measurements and rotating disc electrode measurements provide the sample averaged surface properties, the correlation of results from these two techniques can be useful for the understanding of the catalysts' performance. A striking correlation between the electrocatalytic activity with the material's ability to activate molecular oxygen was observed. The obtained results were rationalized in terms of electronic interaction between the supporting carbon material, and a metallic component. Image 1 • Electrocatalytic activity shows an inverse correlation with the work function. • Direct correlation of the catalyst ability to activate molecular oxygen with ORR. • Work function can be used for the optimization of the ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

Highlights • All the carbon fillers were shear thinning. • Loading of carbon black turned the coating very hydrophobic. • Fullerene CNTs afforded the best electrical and anticorrosive properties. Abstract Four types of carbon filler, carbon black, mixture of carbon black and non-fullerene carbon nanotubes, non-fullerene carbon nanotubes, and purified fullerene carbon nanotubes were compared in a 2-K BPA-Epoxide-Amidoamne. The effect of carbon filler type and loading on the viscosity of coatings as well as mechanical, thermal, electrical, and general coating properties of the cured films were evaluated. General coating properties including pencil hardness, impact resistance, cross-hatch, and pull-off adhesion. Aggregation of carbon fillers at 1.0 wt% resulted in a decrease in film properties. Scanning electron microscope (SEM) was used to observe the surface morphology of a fracture film surface. The storage modulus and crosslink density increased and the maximum tan δ decreased with the increase of filler content. It was found that the most efficient material to enhance the electrical conductivity and anticorrosive properties of nanocomposite coating systems was fullerene CNT. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pd nanoparticles supported on carbon black were encapsulated by mesoporous silica. • The 3D nature of interconnecting pores was confirmed by electron tomography. • The covered catalyst resists sintering but the underlying active phase is accessible. • The catalyst is performant in glucose oxidation due to improved hydrophilicity. Abstract Palladium nanoparticles supported on carbon black were encapsulated in a thin mesoporous silica layer. APTES ((3-aminopropyl) trimethoxysilane) was used as anchoring agent to ensure robust and homogeneous formation of a mesoporous SiO 2 layer around the supported catalyst. This was confirmed by XPS, TEM, electron tomography and nitrogen physisorption measurements. The covered catalyst was tested in the oxidative dehydrogenation of glucose into gluconic acid: the high catalytic activity was maintained in comparison with uncovered catalyst, indicating that the underlying active phase was still available. In addition, the silica layer leads to high temperature stability which prevents the agglomeration of palladium nanoparticles upon sintering conditions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Carbon materials are active in MW-CWPO, combining redox properties and hot spots. • Surface chemistry has a key role in the activity, especially for graphites. • The structure of the materials affects their stability. • AC crumbles down by hot spot formation inside micropores, causing a pop-corn effect. • Graphitic layered structure allows heat dissipation, enhancing catalyst stability. Abstract Several commercial carbon materials have been tested as catalysts in the Microwave-assisted Catalytic Wet Peroxide Oxidation process (MW-CWPO). Two graphites (G-F and G-S), two activated carbons (AC-M and AC-C), two carbon blacks (CB-V and CB-A) and silicon carbide (SiC) were selected due to their MW-absorbing properties. Phenol (100 mg L−1) was used as target pollutant, operating in batch at pH 0 3, 120 °C, 500 mg L−1 catalyst load and the theoretical stoichiometric amount of H 2 O 2 (500 mg L−1). All carbon materials showed to be active in terms of H 2 O 2 decomposition and phenol oxidation. Nonetheless, G-S and AC-M stood out as the most active materials in terms of TOC removal, with values of 94 and 93% TOC elimination, respectively. On the other hand, both carbon blacks and G-F yielded a significantly lower TOC degradation. Surface chemistry seems to rule the activity of graphites, in particular the pH slurry (4.5 for G-S and 8.4 for G-F). The most active catalysts, G-S and AC-M were used in 5 consecutive cycles in order to study their stability. While G-S remained active, AC-M. [ABSTRACT FROM AUTHOR]

Several carbon materials (one carbon nanotubes, two carbon blacks and one home-made carbon aerogel) were covered by thin tin dioxide (SnO 2 ) nanoparticles coatings to improve their resistance against oxidation under the working conditions of Proton Exchange Membrane Fuel Cells. A pretreatment for the nanotubes in acidic media was also performed to improve their dispersion in the reactive medium. The coating was done by a chemical route. Samples were analysed by Scanning Electronic Microscopy (SEM), nitrogen sorption, X-ray diffraction (XRD), Raman spectroscopy, Fourier Transformed InfraRed (FTIR) and X-ray Photoelectron Spectroscopy (XPS). Their electrical conductivities were also measured. Using a reactive medium with a pH value exceeding the point of zero charge of the carbon materials is mandatory to favour electrostatic attractions, and to obtain covering and homogeneous coatings. In this condition, it is possible to reduce the quantity of precursor and to optimise the coating. The intrinsic properties of the carbon materials also influence the characteristics of the coatings. In fact, the least organised carbon materials with high specific surface area and porosity values exhibit homogeneous and covering coatings. On the contrary, organised carbon materials, with few oxygen-containing groups, lead to a smaller quantity and heterogeneous coatings (with some areas of carbon surface uncovered). The pretreatment performed on the nanotubes improves the characteristics of the coatings, even if using significant amounts of precursor remains necessary to obtain a covering and a homogeneous coating. The transformation mechanisms of the precursor into tin dioxide, depending on the pH, value are also discussed. [ABSTRACT FROM AUTHOR]

Differential electrochemical mass spectrometry (DEMS) was used to establish the difference in surface acidity in sulfuric acid solution between commercially available carbon black (Vulcan) and Vulcan which had been chemically modified with concentrated nitric acid (VulcanO). The mass signal for the m / z  = 2 associated with H 2 formation was observed to be influenced by functional groups at the carbon surfaces. Analysis of the mass spectra with the help of the Nernst equation allowed us to quantitatively find the difference in surface pH between the two carbon-based materials in acid media. The elevated concentration of functional groups at the VulcanO surface results in a decrease in the local acidity of the surface under these conditions (0.5 M H 2 SO 4 ), and consequently the hydrogen evolution reaction (HER) is delayed. [ABSTRACT FROM AUTHOR]

We have previously shown that an activated carbon-supported ruthenium catalyst promoted with ReO x (RuRe/AC) is highly active for the hydrodeoxygenation (HDO) of lignin-derived phenols (e.g., guaiacol). In this work, we have investigated the effect of carbon supports on the structure and HDO activity of bimetallic RuRe particles using three different carbon supports, i.e., activated carbon (AC), carbon black (Vulcan carbon, VC), multi-walled carbon nanotube (MWCNT). The MWCNT- and VC-supported catalysts show remarkably enhanced activity and hydrocarbon selectivity for the HDO of a range of phenolic molecules (i.e., guaiacol, eugenol, benzyl phenyl ether) compared to RuRe/AC. STEM-EDS and XPS analyses reveal that bimetallic RuRe particles are more common than monometallic Ru or Re particles in the VC- and MWCNT-supported catalysts, and hexavalent rhenium species are more easily reduced to tetravalent rhenium during the HDO reactions in these catalysts, suggesting that Ru and Re in close proximity are required for the efficient hydrogenolysis of phenols. The formation of bimetallic particles on the AC surface is likely hindered by high microporosity and high surface oxygen functionalities, both of which restrict the mobility of Re and Ru for assembly. [ABSTRACT FROM AUTHOR]

The Arctic shelf is an important carbon reservoir, especially the Chukchi Sea, which plays a vital role in the biogeochemical processes of polar carbon cycles. In this study, we measured the contents of black carbon (BC) and total organic carbon (TOC) in a sediment core of the Chukchi Sea shelf, to evaluate the controlling factors of distribution and burial of BC and TOC. Our results show that the distribution of TOC and BC was strongly influenced by the Pacific Water (PW) inflow, resulting in nearly synchronous change since the early Holocene. The early Holocene (∼9.9 to 8.0 cal kyr BP) was characterized by the minimum of TOC, total nitrogen (TN), and BC, and the most depleted δ13C TOC and δ13C BC values throughout the Holocene, which indicate low primary productivity and low BC supplies under the weak PW flux. The carbon (TOC and BC) burial on the Chukchi Sea shelf was significantly enhanced during the middle Holocene (8.0–4.0 cal kyr BP) due to the rapid increase in PW flux. Since 4.0 cal kyr BP, PW inflow is stable and active, which enables sea ice extent to modulate the stratigraphic variations of BC. In particular, an increase in summer Arctic sea ice during this period may enhance ice-rafted debris and terrestrial carbon supply by promoting erosion of coastal peat soils and permafrost. Our results suggest that PW inflow is the first-order factor controlling Arctic carbon burial during the Holocene, while insolation-induced sea ice increase started playing a role when the PW inflow is active and stable during the late Holocene. • Different source and controlling processes of BC and TOC occurred in the Chukchi Sea shelf. • Carbon burial in the Chukchi Sea shelf was highly enhanced during the middle Holocene. • PW inflow mainly impacts the carbon burial in the Chukchi Sea shelf since the Holocene. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon dots for optical detection of UV ray have been synthesized by a solvothermal reaction. • The synthesized carbon dots are UV light sensitive and can detect UV ray. • The carbon dots can be used as fluorescent detection for UV ray. • The main method and precursor for the synthesis of carbon dots based UV ray detector and their properties have been explored. Carbon dots (CDs) have been developed as prospective nanomaterials for sensing applications owing to their cost-effectiveness, thermal stability, low toxicity, and unique luminescence properties. CDs sensors have been widely used for ion detection but rarely for light detection. Herein, fluorescent CDs from carbon black containing refilled blue ink has been prepared by a solvothermal reaction-assisted straightforward one-pot route under mild temperature conditions. The body color of the as-prepared CDs solution is light brown and shows blue emission under ultraviolet (UV)-light excitation. The UV-light detecting film has been developed by blending the CDs/poly(vinyl alcohol) solution and examined its sensitivity with the increase of UV-light irradiation time. The progression in the body (light-brown to purple) and emission (blue to orange) colors are distinguishable and demonstrates their feasibility in developing the high-performance CDs-based UV detectors. [ABSTRACT FROM AUTHOR]

Photocatalysis assisted oxidation of carbon black was performed using TiO 2 photocatalyst under UV illumination in an atmosphere with NO, O 2 and water vapor at 150 °C. Carbon is oxidized mainly to CO 2 while NO is selectively converted to N 2 . Enhanced O 2 and NO concentrations have a positive effect on the carbon oxidation rate. At a concentration of 3000 ppm NO and 13.3% O 2 in the gas phase the carbon oxidation rate reaches 2.3 μg carbon /mg TiO2 h, at a formal electron/photon quantum efficiency of 0.019. HR SEM images reveal uniform gradual reduction of the carbon particle size irrespective of the distance to TiO 2 photocatalyst particles in the presence of NO, O 2 and H 2 O. [ABSTRACT FROM AUTHOR]

Black carbon plays an important role in climate change. Whereas, accurate measurement of black carbon (also known as elemental carbon (EC)) is still a challenging issue because portion of the pyrolytic carbon produced from the organic carbon (OC) can cause the overestimation of EC when measured by thermal-optical method. As one of the remote regions in the world, the Tibetan Plateau (TP) is characterized as high OC/EC ratio in its atmosphere. In this study, potential influence of relative high OC concentration to EC were investigated at three remote sites (Yaze, Everest and Nam Co) in the TP. The results showed that carbonaceous aerosols from different sources can affect the fraction of OC extracted by methanol. Concentration of OC extracted by methanol had a significantly positive correlation with the reduction of pyrolytic carbon and EC concentrations, indicating that part of OC extracted by methanol can decrease the production of pyrolytic carbon and then reduce the overestimation of EC. After considering this effect, it is shown in this study that actual EC concentration at Yaze, Everest and Nam Co were overestimated by approximately 40.0 ± 12.6%, 28.8 ± 9.1% and 24.8 ± 4.7%, respectively. Accordingly, combined with the overestimation of EC concentration by carbonates, actual ratios of solar energy absorbed by organic carbon to EC were 1.67, 2.33 and 2.78 times those of original ones at Yaze, Everest and Nam Co, respectively. Therefore, warming effect caused by EC on the TP should be lower than that previously estimated. This phenomenon needs to be considered for both in situ study and model simulation in the future. [Display omitted] • Overestimation of EC concentration by OC in aerosols of the TP were investigated. • Fraction of OC extracted by methanol was affected by the sources of aerosols. • EC concentration overestimated by OC of aerosols at Yaze was up to 40.0%. • Fraction of solar energy absorbed by OC relative to EC was underestimated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon composite materials for stealth have aroused great interest. • Carbon-based materials with unique properties have been extensively explored in the field of infrared stealth. • The infrared stealth performance of carbon-based materials is systematically emphasized. • Future prospects and directions for next-generation infrared stealth materials are also proposed. Carbon materials have revolutionized the field of stealth technology with their intriguing properties, such as low weight, large specific surface area, high mechanical strength and good electrical conductivity. The advancement of infrared stealth is particularly critical in order to counter the threat of infrared detection and the deadly strike of precision guidance. The employment of carbon black, carbon nanotubes or graphene offers attractive opportunities to synthesize lightweight, versatile and intelligent infrared stealth materials. This review first introduces brief background information about infrared stealth materials, followed by the analysis of infrared stealth mechanisms. Importantly, we aim to summarize and critically evaluate the hitherto efforts in the design and preparation of carbon-based composites to facilitate the development of infrared stealth waves. The future prospects of carbon-based composites for next-generation infrared stealth materials are presented. [ABSTRACT FROM AUTHOR]

Four carbon materials, spent coffee-ground biochar, carbon black, short CNTs, and nitrogen-doped few-layer graphene (N-graphene) were tested for their functionalization with a commercial carboxylesterase. Their robustness to variations in time and key physicochemical parameters (temperature and pH) was analysed. In general, carbon nanomaterials showed better performance than biochar, both in terms of binding capacity and resilience in harsh conditions, at statistically significant levels. Among the tested materials, functionalized N-graphene also showed the highest level of inhibition of carboxylesterase by pesticide exposure. Therefore, N-graphene was selected for biotechnological application of pesticide scavenging toxicity in T. thermophila , a ciliate bioindicator of water quality. While immobilization of the enzyme was not effective in the case of carbaryl, a methyl carbamate, in the case of the organophosphorus dichlorvos, a 1- or 30-min contact time with a water solution containing 5 times the LC100 - 0.5 mM - allowed 50% and 100% rescue of ciliate survival, respectively. These results suggest that functionalization with carboxylesterase may be of additional benefit compared to bare carbon in water clean-up procedures, especially for highly hydrophilic pesticides such as dichlorvos. [Display omitted] • Four carbon materials were tested for functionalization with a carboxylesterase enzyme.. • Functionalized N-graphene showed the highest degree of inhibition of carboxylesterase by pesticide exposure and generally a good resistance to physicochemical changes. • Functionalized N-graphene was selected for an application of pesticide toxicity scavenging and verified in an ecotoxicological assay with T. thermophila. • Enzymatically functionalized N-graphene showed high capacity to neutralize the toxicity of the organophosphate pesticide Dichlorvos. • Functionalization with carboxylesterase may be of additional benefit compared to bare nano-carbons in water clean-up procedures. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The universal low carbon mass loading was used in capacitive deionization (CDI) for efficient deionized (DI) water production. • Partial desalination performance weakened with increasing carbon mass loading. • CDI cells using YEC-8–5.81 as electrodes produced DI water with a low conductivity of 1.89 μS/cm. • Carbons with a suitable micro- meso pore distribution and high specific capacitance may be a better choice. • 82.2% DI water recovery was achieved under stopped flow (SF) discharge mode. High-purity deionized (DI) water can be widely used in high-end manufacturing fields, but its efficient and energy-saving production is a huge challenge. Here, simple carbon mass loading control was developed for efficient DI water production via advanced capacitive deionization (CDI). Supercapacitor carbon (YEC-8) electrodes with diverse mass loading of 2.50, 5.81, 12.63 and 24.72 mg/cm2 were prepared for desalination. As expected, YEC-8–2.50 acquired the optimal CDI performance. High mass loading of 12.63 and 24.72 mg/cm2 not only caused an overt property drop but also serious wasted materials. Competitively, YEC-8–5.81 achieved a similar volumetric adsorption capacity (VAC) to YEC-8–2.50 as well as made up for the lack of total mass of YEC-8–2.50 and the resultant solution conductivity was as low as 1.89 μS/cm (grade III DI water). This strategy has been successfully extended to other carbon materials and carbons with suitable micro- meso pore distribution and high specific capacitance may be a better choice. Besides, the reverse effect of acetylene black (AB) mass on desalination was verified. To gain a high water recovery (W R), stopped flow (SF) discharge was introduced and realized a high W R of 82.2 %. Meanwhile, cycling tests indicated its splendid cycling stability. This study provides a universal direction for using low mass loading strategy for efficient DI water production. [ABSTRACT FROM AUTHOR]

The colloidal dispersions of Carbon Black (CB) and Graphite powders were prepared in dimethylformamide (DMF) and dimethylsulphoxide (DMSO) as solvent using a facile method. These dispersions were characterized using Ultraviolet-Visible (UV–Vis) and Fourier transform infrared (FTIR) spectroscopy. The Tauc's relation in UV–Vis data affirmed high band gap of 3.32 eV for Graphite suspension in DMSO solvent (GSO) and low band gap of 1.96 eV for CB in DMSO solvent (CBSO). This is due to minimum absorbance of GSO in UV–Vis spectra and inverse relationship of particle size with band gap. The Fourier transform infrared (FTIR) spectroscopy facilitated the study of interaction between solvents (DMSO, DMF) and carbon powders (Graphite, CB). The CB powders showed wider particle size distribution than Graphite powders in Scanning Electron Microscope (SEM) micrographs and even confirmed by span factor calculation. And, X-ray diffraction (XRD) results endorsed amorphous nature of CB powder having short range order in contrast to Graphite powder. Thus, particle size and amorphous nature could be linked with the higher stability of dispersions of CB than that of the Graphite. [ABSTRACT FROM AUTHOR]

We report the time resolved pulsed photoacoustic (PA) spectra of different types of solid carbon blacks obtained from wood charcoal; graphite powder and diesel soot using 532 nm wavelength pulses of duration 30 ps at a repetition rate of 10 Hz. The result of the PA spectra allows us to evaluate the potential use of graphite powder for the identification of trinitrotoluene (TNT) explosive for the first time. Though, TNT has no absorption band at 532 nm (due to higher band gap i.e. 2.7 eV), but its mixture in graphite matrix might reduce the band gap and enable it to absorb 532 nm wavelength due to pi-orbital coupling between graphite and TNT molecules. This is clearly observed concerning downshift in the Raman spectra of the mixture. Further, it is also explained using momentum exchange mechanism due to acoustic phonon waves in their common bands of Raman spectra. Finally, we have studied the different weight percentage of TNT explosive to generalize the response of PA signal. [ABSTRACT FROM AUTHOR]

Different carbon supports are considered to prepare Pt–ZrO 2 /XC-72R carbon black, Pt–ZrO 2 /SWCNTs and Pt–ZrO 2 /MWCNTs electrocatalysts by a solid–state reaction under intermittent microwave heating method using ethylene glycol and NaBH 4 as mixed reducing agents. The prepared electrocatalysts are physically characterized using X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM). Pt particle size decreases in the order: Pt–ZrO 2 /C > Pt–ZrO 2 /MWCNTs > Pt–ZrO 2 /SWCNTs. Cyclic voltammetry, chronoamperometry, chronopotentiometry and electrochemical impedance spectroscopy are applied to investigate the electrochemical performance of the three electrocatalysts for methanol oxidation in H 2 SO 4 solution. CNTs supported electrocatalysts achieve increased methanol oxidation current density and improved stability behaviour during long-time operation when compared to the one containing carbon black. Pt–ZrO 2 /CNTs electrocatalyst also displays lower resistance and higher electrolyte diffusion rate to infer a faster charge transfer process and better electrode accessibility for methanol oxidation. Therefore, carbon nanotubes are suggested as ideal anode electrocatalyst supporting material for the practical application of direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

• High charge propagation of carbon electrode for electrochemical capacitor. • Adenine-derived carbon of high conductivity, good wettability and rich in nitrogen. • Comparison of gravimetric and volumetric metrics for carbon materials. Electrochemical capacitors are attractive power sources, especially when they are able to operate at high frequency (high current regime). In order to meet this requirement their constituents should be made of high conductivity materials with a suitable porosity. In this study, enhanced power and simultaneously high capacitance (120 F g −1 at 1 Hz or 10 A g −1) electrode material obtained from carbonized adenine precursor is presented. A micro/mesoporous character of the carbon with optimal pore size ratio and high surface area was proven by the physicochemical characterization. The beneficial pore structure and morphology resembling highly conductive carbon black, together with a significant nitrogen content (5.5%) allow for high frequency response of aqueous capacitor to be obtained. The carbon/carbon symmetric capacitor (in 1 mol L −1 Li 2 SO 4) has been tested to the voltage of 1.5 V. The cyclic voltammetry indicates a good electrochemical response even at high scan rate (50 mV s −1). The cyclability of the capacitor is comparable to the one operating with commercial carbon (YP50F). The adenine-based capacitor is especially favourable for stationary applications requiring high power. [ABSTRACT FROM AUTHOR]

To identify potential formation mechanisms of water-soluble organic carbon (WSOC) and quantify their contributions to WSOC in urban Guangzhou of south China, a comprehensive campaign was carried out in winter of 2019–2020. During the campaign, WSOC, total carbon (TC), black carbon (BC), water-soluble inorganic ions (WSIIs) and fourteen elements in PM 2.5 were collected using inline instruments. Bulk PM 2.5 and size-segregated particle samples were also synchronously collected using offline instruments for analyzing the dominant chemical components including WSOC, organic carbon (OC), elemental carbon (EC) and WSIIs. In addition, gaseous pollutants (e.g., NH 3 , SO 2 , HNO 3 , NO 2 , O 3) and meteorological parameters were also measured during the same period. PM 2.5 pollution episodes during the campaign period were mainly driven by increased nitrate concentrations. The mass concentration of WSOC increased from 3.9 ± 1.1 μg m−3 on non-episode days to 6.8 ± 0.6 μg m−3 on episode days, although the mass ratio of WSOC to OC in PM 2.5 changed little (<4%). Photochemical processes dominated WSOC formation in the afternoon and aqueous phase chemical processes played the dominant role in the night, from which newly formed WSOC distributed in the condensation mode and the droplet mode, respectively. Source apportionment analysis using positive matrix factorization (PMF) model suggested that on average 35% and 65% of WSOC mass in PM 2.5 were related with the photochemical processes and aqueous phase chemical processes, respectively. Aqueous phase chemical processes were highly affected by nitrate pollution, which was closely related with O 3 pollution. [Display omitted] • Aqueous process of nitrate was the main formation mechanism of WSOC. • Nitrate pollution was mainly related to the hydrolysis of N 2 O 5. • The noon peaks of nitrate and WSOC were related with regional transport. • O 3 has an impact on both aqueous and photochemical processes forming WSOC. [ABSTRACT FROM AUTHOR]

Effects of three geometrically different carbon nanofillers (CNs) namely carbon black, multiwall carbon nanotubes and graphene on the anticorrosive and physico-mechanical properties of hyperbranched alkyd resin (HBA) based coatings were investigated. Hyperbranched urethane alkyd coatings (HBUA) were made by curing the synthesized resin with hexamethylene diisocyanate trimer. All the carbon fillers are treated with a surfactant (Nonidate-P40) to achieve a uniform dispersion. The addition of surfactant treated CNs to HBUA resulted in a significant improvement in the corrosion resistance and mechanical properties in comparison with the neat HBUA coating. Among the HBUA/CN composites, the improvement in corrosion resistance was found to be superior in the case of HBUA/graphene composite. Transmission electron microscope (TEM) clearly indicated the uniform dispersion of carbon nanofillers in the resin. The uniform dispersion of CNs is believed to originate from an interaction of π electron clouds of CNs with the delocalized π electrons of Nonidet-P40 and H-bonding interaction between Nonidet-P40 and the HBA. This type of interaction does not disturb the π electron clouds of MWCNTs as opposed to chemical functionalization strategy. [ABSTRACT FROM AUTHOR]

The photocatalytic oxidation of carbon black on TiO 2 using nitric oxide as an oxidizing agent was investigated. Layer-wise deposited carbon and TiO 2 powder was illuminated with UVA light in the presence of NO at parts per million concentrations in dry and hydrated carrier gas at a temperature of 150 °C. Carbon was photocatalytically converted mainly into CO 2 , and NO mainly into N 2 . Carbon oxidation rates of 7.2 μg/h/mgTiO 2 were achieved in the presence of 3000 ppm NO. Under these experimental conditions in the absence of molecular oxygen, formation of surface nitrates causing TiO 2 photocatalyst deactivation is suppressed. Addition of water enhances surface nitrate formation and catalyst deactivation. NO and carbon particulate matter are air pollutants emitted by diesel engines. Elimination of soot collected on a diesel particulate filter through oxidation is a demanding reaction requiring temperatures in excess of 250 °C. The present study opens perspectives for a low-temperature regeneration strategy for the diesel particulate filter that simultaneously performs DeNO x reactions. [ABSTRACT FROM AUTHOR]

In this work, industrial black liquor (BL) was directly used to prepare activated carbons with high surface area and large pore volume through K 2 CO 3 activation. The effect of activation temperature on the properties and the Cr(VI) removal performance of activated carbons were investigated. For comparison, the purified lignin (PL) was also investigated. The specific surface area and the total pore volume of BL derived carbon prepared at 800 °C (CBLS 800) were 1335.58 m2/g and 1.79 cm3/g, while those of PL derived carbon prepared at 900 °C (CPL 900) were 1715.16 m2/g and 1.12 cm3/g. The Cr(VI) removal process conforms to the pseudo-second-order kinetic model, indicating that the adsorption process is mainly controlled by chemical interaction. The fitting of isotherm was more consistent with Langmuir model. The maximum adsorption amount of Cr(VI) on CBLS 800 and CPL 900 was 669.70 and 645.73 mg/g at 45 °C and pH 2.0, respectively. The negative Δ G ° and positive Δ H ° confirmed that the adsorption of Cr(VI) onto CBLS 800 and CPL 900 was an endothermic and spontaneous process. The removal mechanism of Cr(VI) mainly includes three aspects: intra particle diffusion, electrostatic attraction and adsorption-coupled reduction. This work not only provides a theoretical basis for transforming BL into functionalized biochar materials, but also makes the efficient removal of Cr(VI) from wastewater possible. [Display omitted] • K 2 CO 3 activation was used to prepare black liquor-derived porous carbon (CBLS). • The specific surface area of CBLS 800 is 1335.58 m2/g. • The maximum adsorption amount of Cr(VI) on CBLS 800 is 669.70 mg/g. • The removal mechanism of Cr (VI) is mainly adsorption-coupled reduction. • The inherent alkali plays a role of self-chemical activation. [ABSTRACT FROM AUTHOR]