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[Display omitted] • A scalable, one-step strategy to synthesize binder-free catalysts is proposed. • Ru/NiFeOOH/NFF exhibits superior OER activities in alkaline media. • Correlation between electronic interaction and OER performance is established. • Ru/NiFeOOH/NFF achieves long-term stability over 400 h at 100 mA cm−2. Oxygen evolution reaction (OER) is a bottleneck half-reaction of water splitting due to its sluggish kinetics involving four-electron transfer process. Developing a facile strategy for synthesis of low-cost and highly efficient OER catalysts is crucial but still very challenging. Herein, a bimetallic substrate induction (BSI) strategy to integrally construct supported metal catalysts (SMCs) as binder-free electrode in one step is proposed. As-used NiFe foam (NFF) not only plays the roles of the metal source and the reducing agent for in-situ growth of NiFeOOH supported Ru nanoparticles, but also guarantees the strong interaction between the SMCs and NiFe substrate. Consequently, the self-supported Ru/NiFeOOH/NFF electrode exhibits extraordinary OER performance in both alkaline salty water and seawater electrolytes. It can achieve the industrial current density of 500 mA cm−2 in 1 M KOH and 1 M KOH seawater at overpotentials of 285 and 330 mV, respectively, together with robust durability for over 400 h under current density of 100 mA cm−2. The combined theoretical and experimental investigations reveal that the in-situ formed metal-supported interaction accounts for both the optimal electronic states and the chemical stability. Furthermore, this BSI strategy can be applied in natural seawater for the scalable preparation of SMCs, demonstrating the universal applicability of BSI strategy. [ABSTRACT FROM AUTHOR]

The heat desorption of styrene from adsorbents is impracticable owing to its spontaneous polymerization under heating conditions. However, the feature also brings a potential promoting effect on styrene adsorption. Therefore, it is expected to develop the non-regenerative adsorbents with large adsorption capacity by strengthening the polymerization effect. In this work, C–Cl grafted silica gel adsorbents were prepared by introducing (Chloromethyl)dimethylchlorosilane (CMDMCS) and FeCl 2 into silica gel. The C–Cl grafted silica gel exhibited excellent styrene adsorption performance, its adsorption amounts for styrene were 4.67 times and 9 times of unmodified silica gel under dry air condition and high humidity condition (RH = 80%), respectively. In addition, the adsorption of styrene on C–Cl grafted silica gel was almost unaffected by the presence of toluene. The characterization of adsorbents after styrene adsorption indicated that the improvement of adsorption capacity of C–Cl grafted silica gel for styrene can be attributed to atom transfer radical polymerization (ATRP) of styrene molecules on modified silica gel during adsorption process. [Display omitted] • C–Cl grafted SiO 2 adsorbents were prepared by introducing CMDMCS and FeCl 2. • The adsorption capacity of SiO 2 -1.5 for styrene was 4.7 times of SiO 2. • The adsorption of styrene on C–Cl grafted SiO 2 was almost unaffected by toluene. • C–Cl grafted SiO 2 showed excellent moisture resistance for styrene adsorption. • ATRP occurred during the adsorption process of styrene on C–Cl grafted SiO 2. [ABSTRACT FROM AUTHOR]

Mesocarbon microbeads (MCMBs) are attractive precursors for high-density, high-strength polycrystalline graphite due to their self-sintering capability. They have the shape of a standard sphere and stack in a completely random orientation during compaction, thereby leading to an isotropic texture. In this paper, MCMB-based graphite shows better isotropic property than commercial nuclear graphite, as demonstrated by a coefficient of thermal expansion-based isotropy ratio of 1.00. It was found that variations in apparent density within block are approximately 2–5% in graphitized artifacts. The variation of flexural strength within block is small, revealing excellent homogeneity of MCMB-based graphite. Density distribution measurement indicates that artifacts produced in the same batch also have low variation from block to block. Furthermore, the flexural strength of this material is greatly influenced by heat treatment temperature and mean particle size. The fracture mechanism is also shown by a detail examination of fracture surfaces. These results may help to gain a better understanding of MCMB-based graphite. [ABSTRACT FROM AUTHOR]

Poly(triazine imides) intercalated with Li+ and X− (PTI/X, X=Cl or Br), which are described widely as crystalline polymeric carbon nitrides, were synthesized in a facile manner by heating a mixture of melamine and LiX. This method has the advantages of low cost, scalable production, and high efficiency. Importantly, both PTI/Cl and PTI/Br exhibit an enhanced photocatalytic performance compared to conventional graphitic polymeric carbon nitride in the degradation of rhodamine B under visible-light irradiation because of their higher visible-light-harvesting ability and charge carrier separation efficiency. [ABSTRACT FROM AUTHOR]

Graphite materials are used in high-temperature gas-cooled reactor (HTR) as moderator and reflector. Nuclear graphite is currently manufactured using coke as the filler; however, improvements in the performance of nuclear graphite are anticipated in order to enhance the safety and lifetime of HTRs. Natural microcrystalline graphite (MG), which is a metamorphic product of coal, is an emerging candidate as filler material. This paper proposes the approach of preparing isotropic graphite using MG fillers. The characterization results of MG ores and purified powder indicate a polycrystalline and near-isotropic structure of MG particles. Thus, near-isotropic graphite with an isotropy ratio of 1.10–1.15 can be easily obtained via cold isostatic pressing. The thermal diffusivity of MG-based green body is much higher than that of coke-based one, therefore facilitates the baking step. The advantages of MG-based graphite also include a high degree of graphitization, and a low coefficient of thermal expansion, both of which are highly beneficial to nuclear applications. As a result, MG exhibits a large potential for the application in isotropic nuclear graphite. [ABSTRACT FROM AUTHOR]

Micro-mesoporous carbon nanofiber membranes with improved graphitic structure are produced by electrospinning, catalytic graphitization and NH 3 treatment. Exceptionally ultrathin curved graphitic nanolayers and developed micro-mesoporous structure with narrow aperiodic mesopore size distribution (3–10 nm) are grown simultaneously in nano-scaled one-dimensional structure. Specific surface area is as high as 1326 m 2  g −1 . Mesopore volume with pore widths of 3–10 nm exhibiting highly linear dependency on the graphitization degree can be precisely tuned from 0.025 to 0.186 cm 3  g −1  by adjusting heat-treatment temperature and transition metal content in the template-free synthesis, due to limitation of nano-scaled fiber diameter. [ABSTRACT FROM AUTHOR]

Highlights: [•] Graphene oxide-embedded electrospun porous carbon nanofiber webs were prepared. [•] GO-PCNF had higher mesopore ratio and electrical conductivity due to GO embedment. [•] GO-PCNF electrode exhibited better capacitive deionization performance than PCNF. [ABSTRACT FROM AUTHOR]

Highlights: [•] Activated electrospun carbon nanofibers were oxidized by acid treatment. [•] Surface polarity of nanofibers increased with surface oxygen content increasing. [•] Enhanced surface polarity led to higher water adsorption capacities on nanofibers. [•] Surface oxidation improved the adsorption tendency for butanone over benzene. [Copyright &y& Elsevier]

Abstract: Mildly expanded graphite (MEG) was synthesized by using perchloric acid as both intercalating agent and oxidizing agent. Its performance as anode material for lithium ion battery was investigated. SEM, XRD, TEM, nitrogen adsorption and TGA/DSC were used to characterize the sample. Charge/discharge tests show that the MEG exhibits a rate capacity as high as 397mAh/g at 0.2C and 250mAh/g at 1.6C. [Copyright &y& Elsevier]

Abstract: Microporous carbon ultrafine fibers with different diameter were prepared by electrospinning from resole-type phenolic resin, followed by heat curing and one-step carbonization, and their adsorption performance for benzene and water was evaluated. Average diameter of as-spun fibers changed from 1.1 to 0.33μm with increasing dimethylformamide content in the spinning solution, caused by more fiber divisions. The carbon ultrafine fibers with smaller diameter exhibited enhanced benzene adsorption and diminished water adsorption due to improved specific surface area, micropore volume and hydrophobicity. In addition, the relatively developed hydrophobicity of the prepared carbon ultrafine fibers resulted in much higher adsorption tendency for benzene over water, in comparison to common polyacrylonitrile-based electrospun activated carbon nanofibers. [Copyright &y& Elsevier]

Activated carbon nanofibers (ACNFs) were prepared by electrospinning polyacrylonitrile solutions, and subsequent steam activation process. The ACNFs were characterized by scanning electron microscope, X-ray photoelectron spectroscopy and nitrogen adsorption at 77 K. The adsorption equilibrium data for benzene and ethanol were obtained by using static vapor adsorption system. As-prepared ACNFs demonstrate higher adsorption capacities for volatile organic compounds (VOCs) than activated carbon fibers (ACFs) by virtue of smaller diameter and more available adsorption sites on the surface. The adsorption performance of ACNFs increases with the burn-off, as a result of the increased microporosity. In addition, it is noteworthy that surface chemistry has an important effect on the adsorption of polar VOCs. The ACNF with higher oxygen content has a stronger adsorption tendency for ethanol. [ABSTRACT FROM AUTHOR]

Abstract: Porous graphitic carbons (PGC) are synthesized to be used in internal parallel hybrid devices. The hybrid devices are assembled with a LiFePO4 cathode, and an anode based on a mixture of PGC and Li4Ti5O12. Then the hybrid devices are characterized by galvanostatic charge/discharge, rate charge/discharge and cycle performance testing. The results show that PGC hybrid devices possess better performance than the commercial activated carbon hybrid device. Moreover, the internal parallel hybrid device with 25% PGC, denoted as T3P1F, exhibits an optimal performance with high energy density, high power density and stable cycling performance. [Copyright &y& Elsevier]

Abstract: We demonstrate the potential use of asphalt emulsions as a binder for the preparation of polycrystalline graphite. An emulsion mixing method was adopted to create the natural microcrystalline graphite and asphalt binder mixture, and graphite samples with a bulk density of 1.7g/cm3 and a flexural strength of ca. 22MPa were prepared. This approach is advantageous because of the uniformity of the asphalt coating, and it also reduces the use of coal tar pitch. [Copyright &y& Elsevier]

Graphene/ Bi2 WO6 composites have been synthesized by hydrothermal reduction at 160°C for 24 h using ethanol as the reducing agent. All as-prepared composites were characterized using X-ray diffraction ( XRD), UV-vis diffuse reflectance spectroscopy, FT- IR spectroscopy, Raman spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption, and photocatalytic activity evaluation. The effective charge separation of graphene/ Bi2 WO6 composites was caused by the electrical conduction of graphene which is the most important factor. The results have proved the formation of interfacial contact between graphene nanosheets and Bi2 WO6 nanoplates. The adsorptivity for azo dyes was enhanced greatly with the introduction of graphene. The oxy-functional groups located at the edges of graphene were responsible for the enhanced adsorptivity. As-prepared graphene/ Bi2 WO6 composites exhibited enhanced light absorption from UV to visible-light region. In addition, the introduction of graphene would also result in smaller crystalline size and lower crystallinity of Bi2 WO6. Graphene/ Bi2 WO6 composites containing an appropriate amount of graphene were proved to exhibit higher adsorptivities and photocatalytic activities for azo dyes. High photocatalytic activities of graphene/ Bi2 WO6 composites were considered to be the synergetic effects of high adsorption, high light absorption, and high electrical conduction induced by the introduction of graphene. [ABSTRACT FROM AUTHOR]

Abstract: Electrospun porous carbon nanofibers fabricated by electrospinning and steam activation were functionalized by spontaneous grafting of phenylsulfonic acid (PSA) groups. SEM and Raman observation suggested that modified electrospun nanofibers did not exhibit distinct changes of surface morphology and intrinsic graphitic structure. Nitrogen adsorption showed decrease in surface area and pore volume of modified carbon nanofibers. XPS and elementary analysis were conducted to characterize the surface chemistry of carbon nanofibers. The hydrophilic character was measured by the contact angles and static adsorption isotherms of water. The adsorption isotherms of benzene and butanone showed that the increasing hydrophilicity led to enhancement of adsorption performance for butanone on carbon nanofibers, indicating that the adsorption selectivity to hydrophilic organic compounds was improved. [Copyright &y& Elsevier]

Abstract: Activated carbon nanofibers (ACNFs) were firstly fabricated by stabilizing, carbonizing and activating electrospun-derived polyacrylonitrile (PAN) nanofibers. Then the graphite carbon nanofibers (GPNF-1900, GPNF-2400) were achieved by graphitization at 1900°C and 2400°C. The GPNFs and ACNFs were characterized by SEM, FTIR, Raman and nitrogen adsorption at 77K. The adsorption and oxidation of NO at room temperature (30°C) were investigated. The results showed that GPNF with porous graphitic structure can improve dramatically the catalytic oxidation of NO at room temperature. The steady conversion ratio of NO to NO2 over the ACNFs, GPNF-1900 and GPNF-2400 was 11%, 38%, 45%, respectively, which revealed that GPNFs would be promising catalysts in catalytic oxidation of NO at room temperature. [Copyright &y& Elsevier]

Abstract: In the present study, we prepared flexible phenolic resin fabrics and corresponding porous carbon fabrics through electrospinning and successive curing and carbonization of resol/ethanol solutions. The addition of high-molecular-weight polyvinyl butyral (PVB) is essential for the stable fabrication of bead-free resol fabrics. Due to a high evaporation rate of ethanol and non-linear molecule structure of resol, the electrospun fabrics consist of entangled high aspect ratio ribbons instead of round fibers. The resol fabrics can be simply cured by heating at low temperature in air. Further carbonization at different temperatures resulted in flexible porous carbon fabrics with different specific surface area, which reached a maximum value of 855m2/g after heat treatment at 1000°C. These phenolic resin-based free-standing porous carbon fabrics would be promising in adsorption and electrochemical applications. [Copyright &y& Elsevier]

Abstract: Adsorption of water vapor on graphene nanosheets (GNS) derived by vacuum-promoted low-temperature exfoliation method was investigated using a volumetric system. The pristine and thermally modified GNS were characterized with scanning electron microscopy (SEM) observation, Fourier transform infrared (FT-IR) analysis and nitrogen adsorption–desorption. The results show that the absorbed amount of water vapor against the pristine GNS can reach 249cm3/g at 20°C, and the capability of water vapor adsorption was weakened by heat treatment at 500°C and 700°C, the isosteric heat of water vapor adsorption against GNS is 42.6kJ/mol based on the adsorption isotherms at 10°C and 30°C. [Copyright &y& Elsevier]

Abstract: Porous carbons are derived by carbonizing coal tar pitch with one dimension non-silica template (needle-like nano-sized MgO). The samples are characterized by nitrogen adsorption at 77K and XRD analysis. The electrochemical performances for supercapacitor are evaluated in a 6M KOH aqueous solution. The results show that the as-prepared porous carbons possess abundant mesopores of 3.7–6.5nm. With air stabilization process, the samples possess more micropores, contributing nearly 50% of surface areas. The porous carbon with large template content through air stabilization possess a high surface area of 864m2 g−1. For supercapacitors electrode material, the porous carbon shows a high capacity and excellent power performance, retaining 100Fg−1 even at a current density of 30Ag−1. [Copyright &y& Elsevier]

Abstract: ZnO/SiO2 gel composites with different active component loading were prepared by sol–gel method combined with ambient drying process, followed by thermal treatment. The gel composites were characterized by scanning electron microscopy (SEM), nitrogen adsorption, X-ray diffraction (XRD), FTIR and X-ray photoelectron spectroscopy (XPS), and their performances for H2S removal were evaluated by dynamic testing at room temperature. The as prepared materials exhibited high surface area with multimodal pore size distributions in micropore and mesopore region. The porous properties were significantly influenced both by the ZnO loading ratio and the treated temperature. The gel composites showed a high performance for H2S removal, with the highest H2S adsorption capacity of 96.4mg/g for the sample treated at 400°C with 30wt% ZnO. Both physisorption and the active phase reactivation governed the H2S removal process. It needs to optimize the composites’ porous structure and active component loading amount. [Copyright &y& Elsevier]

Abstract: Mesoporous carbons are prepared from a mixture of the soluble starch with needle-like nano-sized Mg(OH)2 particles. The samples structures are characterized by TEM, nitrogen adsorption at 77K and XRD. The electrochemical performance for electrochemical capacitors is evaluated in a 6M KOH aqueous solution. The resultant carbons show a disordered pore structure with interweaving straight nano-tunnels that resembled the shape of the template, and possess a high surface area more than 1000m2 g−1 and a large pore volume. The special one dimensional morphology of templates cause a graphitization effect on the carbon in partial region, different from catalytic graphitization mechanism of transition metal particles. Due to those characteristics, the samples exhibit good electrochemical performances used for electrochemical capacitors electrode, especially excellent power capability. The sample carbonized at 950°C for 6h retain a capacitance of 126Fg−1 even at a high current density of 40Ag−1. [Copyright &y& Elsevier]

Abstract: A novel hierarchical carbon nanotube/bamboo charcoal (CNT/BC) composite material was prepared by growing CNTs onto low-cost bamboo charcoal (BC) with the CVD method. Adsorption of Pb2+ in aqueous solution with a CNT/BC composite was investigated. The results showed that the CNT/BC composite exhibited higher adsorption capacity and faster uptake rate towards aqueous Pb2+ than the pristine BC. The isotherms and kinetics of adsorption can be well described by the Langmuir and pseudo-second-order models, respectively. The CNT/BC composite prepared possesses much better performance for Pb2+ adsorption, higher capacity and rate of adsorption, than other carbon adsorbents, such as activated carbons and CNTs. [Copyright &y& Elsevier]

Abstract: Graphite artifacts were prepared using mesocarbon microbeads (MCMBs) with two different extents of oxidation, lightly oxidized MCMBs (M-LO) and highly oxidized MCMBs (M-HO). Cold isostatic pressing at 200MPa was used in the formation process. Physical properties of the obtained artifacts prepared with two raw materials are quite different, the reason can be found in their pyrolysis behavior and sintering behavior. Thermogravimetry–mass spectrometer results show that H2, CH4, CO2 and H2O are the common gaseous products, however, between 400 and 600°C the M-LO may generate lightweight hydrocarbon component which was confirmed by thermogravimetry–infrared spectroscopy. A remarkable difference between the flexural strength of M-LO and M-HO was explained by the microstructure evolution observed with in situ scanning electron microscopy. For M-LO, cracks are mainly transgranular, giving little chance for interconnection, while in M-HO, cracks are mainly intergranular and may connect to form long cracks. A mechanism of crack formation caused by inhomogeneous shrinkage was proposed. [Copyright &y& Elsevier]

Abstract: The adsorption of dimethyl sulfide from an aqueous solution by a cost-effective bamboo charcoal from Dendrocalamus was studied in comparison with other carbon adsorbents. The bamboo charcoal exhibited superior adsorption on dimethyl sulfide compared with powdered activated carbons at different adsorbent dosages. The adsorption characteristics of dimethyl sulfide onto bamboo charcoal were investigated under varying experimental conditions such as particle size, contact time, initial concentration and adsorbent dosage. The dimethyl sulfide removal was enhanced from 31 to 63% as the particle size was decreased from 24–40 to >300 mesh for the bamboo charcoal. The removal efficiency increased with increasing the adsorbent dosage from 0.5 to 10mg, and reached 70% removal efficiency at 10mg adsorbed. The adsorption capacity (μg/g) increased with increasing concentration of dimethyl sulfide while the removal efficiency decreased. The adsorption process conforms well to a pseudo-second-order kinetics model. The adsorption of dimethyl sulfide is more appropriately described by the Freundlich isotherm (R 2, 0.9926) than by the Langmuir isotherm (R 2, 0.8685). Bamboo charcoal was characterized by various analytical methods to understand the adsorption mechanism. Bamboo charcoal is abundant in acidic and alcohol functional groups normally not observed in PAC. A distinct difference is that the superior mineral composition of Fe (0.4wt%) and Mn (0.6wt%) was detected in bamboo charcoal—elements not found in PAC. Acidic functional group and specific adsorption sites would be responsible for the strong adsorption of dimethyl sulfide onto bamboo charcoal of Dendrocalamus origin. [Copyright &y& Elsevier]

Abstract: Porous carbon nanofibers (PCNFs) were fabricated by stabilization, carbonization and activation with steam after electrospinning the polymer solution of polyacrylonitrile (PAN) in N,N-dimethylformamide (DMF). The nitrogen adsorption and desorption at 77K showed that PAN-based PCNFs are highly microporous. Removal of NO with PCNFs at room temperature was investigated. The ratio of NO removed by PCNFs is higher than 60% when the inlet NO concentration was 20ppm with 0.10g of sample, and NOx (NO+NO2) cannot be detected when the inlet NO concentration was 2ppm within 24h. The mechanism sequence is supposed to be NO adsorption, catalytic oxidation to NO2 and part reduction to N2 by PCNFs due to greater carbon surface area and a higher quantity of nitrogen species. Thus, PCNFs would be effective for purging low concentration NOx at room temperature. [Copyright &y& Elsevier]

Abstract: A strain of bacterium (BC027) for quinoline degradation was inoculated on the activated bamboo charcoal (ABC) substrate. SEM observation showed that the bacterium grew well on the charcoal substrate and thus obtained biologically activated bamboo charcoal (BABC). The investigation on quinoline removal showed that BABC has greater capacity for removing quinoline than ABC or dissociate BC027. The removal ability of BABC is influenced by initial concentration and domestication process. Adsorption of carbon substrate only occurred at the beginning stage, while it had no effect on the bacterium inoculation and activity. The bacteria enhanced the treatment capacity of ABC and prolonged its usage life. [Copyright &y& Elsevier]

Abstract: Photoactive TiO2 was homogeneously mounted on PAN-based activated carbon cloths (ACCs) by a process of dip-coating and subsequent annealing in nitrogen atmosphere. The crystallinity of TiO2 and pore structure of hybrids was characterized by XRD and N2 adsorption. The adsorption and photocatalytic activity for TiO2-mounted ACC towards methylene blue (MB) solution was investigated. The results showed that the coating of TiO2 gel resulted in a marked decrease in specific surface area and pore volume from the pristine ACC, which was recovered gradually with increasing treatment temperature. Besides crystallinity of TiO2 can be modified by heat treatment, its pore structure can be postulated by adding different amount of polyethylene glycol (PEG). Both pore structure of hybrids and crystallinity of TiO2 as well as the carbon residue produced by PEG pyrolysis had effects on their adsorptive and photocatalytic performances of TiO2-mounted ACCs. It would be a promising technology to integrate adsorption and photocatalysis for TiO2-mounted ACCs. [Copyright &y& Elsevier]

Supercritical water (SCW) has been employed as an efficient activating agent for the preparation of activated carbon microspheres (P-ACS) with developed mesopores from phenolic-resin. Several processing factors that influenced the activation reaction, including activation temperature, activation duration, supercritical pressure and water flow rate were investigated. Increasing activation temperature and duration lead to larger porosity and higher specific surface area as demonstrated in the samples. Supercritical pressure change has little effect on the activation; however, there are indications that a slight increase in mesoporosity can be obtained when the pressure was raised to 36 MPa or higher. Higher water flow rate slightly enhanced the development of microporosity but had little effect on the mesoporosity. Compared with the traditional steam activation, SCW activation can produce P-ACS with more mesoporosity and higher mechanical strength. [Copyright &y& Elsevier]

The breakthrough of low concentration methyethylketone (MEK) and benzene vapors in beds packed with rayon-based activated carbon fiber (ACF) with different surface areas was investigated. The breakthrough characteristics depend on the properties of the ACF and the vapors, as well as on the adsorption conditions. The results of dynamic adsorption in an ACF bed were consistent with those of equilibrium adsorption by gravimetric methods. The breakthrough adsorption indicates that ACF, with an appropriate surface area, could be utilized in controlling volatile organic compounds (VOCs) in indoor air. [Copyright &y& Elsevier]

Viscose rayon fabric impregnated with (NH 4 ) 2 HPO 4 were carbonized in 200 cm 3 /min N 2 at 5°C/min with a residence time of 1 h at 850°C and then activated with 200 cm 3 /min CO 2 at 850°C for different burnoffs. The pore structure of all samples was characterized by N 2 adsorption at 77 K. Adsorption of methy-ethyl-ketone (MEK) and benzene vapor on the adsorbents was measured by gravimetric method. The results show that viscose rayon-based activated carbon fiber (ACF) exhibited narrower microporosity and higher micropore volume as compared with that activated by steam. ACFs prepared in this way have higher adsorption capacity for low concentration VOCs. [ABSTRACT FROM PUBLISHER]

The adsorption of polar methy-ethyl-ketone (MEK) and non-polar benzene vapors on viscose rayon-based activated carbon fiber (ACF) was investigated. The pore texture and surface composition of ACF were characterized by nitrogen adsorption at 77 K and X-ray photoelectron spectroscopy (XPS), respectively. Gas adsorption on the samples was measured by the gravimetric method and the Dubinin–Radushkevich (DR) equation was used to fit the experimental adsorption isotherms. The experimental results show that ACF with different pore texture and surface composition exhibited different adsorption and desorption behavior for polar and non-polar vapors. The effect of adsorbate polarity on the adsorption capacity at lower concentrations was more significant in the case of adsorbents with a smaller surface area. It was found that evacuation treatment greatly increased the adsorption rate. [ABSTRACT FROM AUTHOR]

The pore microstructures in two viscouse rayon-based ACF samples were characterized by nitrogen adsorption and HRTEM. For TEM, a two-dimensional fast Fourier transform (FFT) of the original TEM images was performed, and pores in different size ranges were extracted by the inverse FFT (IFFT) operation. The surface fractal dimensions of the samples were evaluated by using both N2 adsorption and TEM image analysis. The results show that TEM can portray the shapes of the pore, and it can give a quantitative evaluation of surface irregularity that is consistent with nitrogen adsorption results. [Copyright &y& Elsevier]

Waterborne epoxy (WEP) coatings with enhanced corrosion resistance were prepared using graphene oxide (GO) that was obtained from kish graphite, and amino-functionalized graphene oxide (AGO) was modified by 2-aminomalonamide. The structural characteristics of the GO and AGO were analyzed using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). And the anti-corrosive performance of waterborne epoxy-cased composite coatings with different addition amounts of AGO was investigated using electrochemical measurements, pull-off adhesion tests, and salt spray tests. The results indicate that AGO15/WEP with 0.15 wt.% of AGO has the best anti-corrosive performance, and the lowest frequency impedance modulus increased from 1.03 × 108 to 1.63 × 1010 ohm·cm−2 compared to that of WEP. Furthermore, AGO15/WEP also demonstrates the minimal corrosion products or bubbles in the salt spray test for 200 h, affirming its exceptional long-term corrosion protection capability. [ABSTRACT FROM AUTHOR]

Abstract: Phenolic resin-based porous carbon nanofibers (PCNFs) with large surface area and narrow pore size distribution have been successfully prepared using novolac-type phenolic resin as precursor. The high molecular weight precursor was first synthesized in this study, then was dissolved in methanol. The PCNFs were finally obtained through electrospinning the phenolic resin polymer solution followed by successive curing and carbonization without activation. The N2 adsorption/desorption isotherms reveal that the PCNFs have high specific surface area about 812m2/g, the pore size falls in the range of 0.4–0.7nm and the pore volume is 0.91cm3/g. The vapor adsorption testing demonstrated that PCNFs exhibited different adsorption performance for ethanol and water. [Copyright &y& Elsevier]

Abstract: Mesoporous carbon nanosheets with high surface areas and large total pore volumes were prepared using tubular halloysite as inorganic matrix and furfuryl alcohol (FA) as carbon precursor by a template-like method. Field emission scanning electron microscope, high-resolution transmission electron microscopy (HRTEM) and nitrogen adsorption analysis were employed to characterize the morphologies and pore structures of the samples. It is found that tunable mesoporous carbons can be obtained by adjusting FA volume concentration. Lowering FA concentration leads to an increase in the BET specific surface area and narrowing of the mesopore size distribution. [Copyright &y& Elsevier]

Abstract: Porous carbon was prepared from deoiled asphalt by conventional NaOH activation process and by the combination of nano-sized MgO template method and NaOH activation process. The electrochemical properties used as supercapacitors electrode material were evaluated in 7M KOH aqueous solution. Porous carbon sample obtained by NaOH activation possessed more micropores and higher specific surface area, resulting in a higher specific capacitance of 235Fg−1 at low charge–discharge current of 50mAg−1. For the combination method, the resultant carbons possessed higher capacitance and good capacitance maintaining at high current, with a capacitance of nearly twice as that of the former at current density of 10Ag−1, due to their abundant mesopores. [Copyright &y& Elsevier]

Ultrafine carbon fiber webs were prepared from oxidatively stabilized electrospun poly(acrylonitrile) fibers, followed by carbonization or by further activation with steam. Capacitive de-ionization was evaluated in the batch mode. It was found that the webs exhibited considerable electrical adsorption, which was enhanced by activation with a faster electrosorption rate and a higher electrosorption capacity. [ABSTRACT FROM AUTHOR]

Ultrafine carbon fiber webs were prepared from oxidatively stabilized electrospun poly(acrylonitrile) fibers, followed by carbonization or by further activation with steam. Capacitive de-ionization was evaluated in the batch mode. It was found that the webs exhibited considerable electrical adsorption, which was enhanced by activation with a faster electrosorption rate and a higher electrosorption capacity. [ABSTRACT FROM AUTHOR]

Ultrafine carbon fiber webs were prepared from oxidatively stabilized electrospun poly(acrylonitrile) fibers, followed by carbonization or by further activation with steam. Capacitive de-ionization was evaluated in the batch mode. It was found that the webs exhibited considerable electrical adsorption, which was enhanced by activation with a faster electrosorption rate and a higher electrosorption capacity. [ABSTRACT FROM AUTHOR]

Microcrystalline graphite (MG) is a major form of natural graphite and an important raw material with various applications in advanced technologies, such as lithium-ion battery anodes and isotropic graphite filler particles. MG is known to be an aggregate of graphite crystallites with a lateral dimension of less than 1 μm. However, the microstructure of MG remains unclear. In this study, we report the porous structure of a purified Chinese MG with an apparent density of 1.3–1.4 g/cm3. MG typically contains many microslits that are approximately 1–2 μm in length and up to 200 nm in width. The microslits provide MG with a stronger ability to accommodate c-axis thermal expansion than Mrozowski cracks, resulting in a low coefficient of thermal expansion (CTE) of approximately 2 × 10−6/K. This unique thermal expansion behavior makes MG a promising filler material for developing artificial graphite with a low CTE, and enables the modulation of the CTE of nuclear graphite. [Display omitted] [ABSTRACT FROM AUTHOR]

Na-ion capacitors (NICs) are promising energy storage devices in virtue of their merits in combining the high energy densities of secondary batteries and the high power densities of supercapacitors. However, it is still very challenging to achieve a balanced energy-power performance in NIC device due to the kinetic imbalance between the battery-type anode and the capacitive-type cathode. In this work, an NIC device based on carbon materials for both anode and cathode has been reported. As-prepared (polyimide/graphene oxide)-derived carbon (PIGC) anode material shows excellent rate capability, which can deliver a specific capacity of 110 mAh g−1 at high current densities of 5 A g−1. In addition, the N, B co-doped expanded reduced graphite oxide (NBEG) cathode demonstrates a high specific capacitance of 328 F g−1. Due to the improved rate capability of PIGC anode and specific capacitance of NBEG cathode, the imbalance on the energy and power densities between anode and cathode is well addressed. As-assembled PIGC//NBEG device can deliver an energy density of 55 W h kg−1 even at a high power density of 9500 W kg−1. The energy-power properties of PIGC//NBEG are superior to many state-of-the-art NIC devices that using carbon or non-carbon based electrodes. This work offers not only a promising device configuration with superior energy-power properties, but also a guidance for the design strategies on electrode materials for high-throughput energy storage systems. Image 1 • Carbon-based materials were used in both electrodes for sodium ion capacitors. • The imbalance on the energy/power densities of anode and cathode is well addressed. • PIGC//NBEG delivered an energy density of 55 W h kg−1 at a power density of 9500 W kg−1. [ABSTRACT FROM AUTHOR]

Single atomic metal (SAM) doping is reported as an effective strategy to promote the electrochemical property of carbon‐based anode materials for high‐power sodium‐ion batteries (SIBs). However, the effects of SAM with different configurations on solid electrolyte interphase (SEI) and energy storage mechanism of Na+ are not revealed. Herein, Cr single atoms (CrSAs) are reported with controllable configurations (Cr–N4 or Cr–N2) implanted on the N, P co‐doped carbon (NPC) anode materials (denoted as CrN4SAs/NPC or CrN2SAs/NPC). The CrN4SAs/NPC anode displays a high specific capacity (318.2 mAh g−1 at 0.05 A g−1) and outstanding rate performance (145.1 mAh g−1 at 5 A g−1), better than those of CrN2SAs/NPC and NPC. The superiority is originated from the difference of SEI and the energy storage mechanism of sodium ions during electrochemical process, which are unveiled through ex situ characterization and theoretical calculation. The full cell assembled with CrN4SAs/NPC anode and Na3V2(PO4)2F3@C cathode displays a high energy density at a high power density. [ABSTRACT FROM AUTHOR]

Fibrous carbon materials have a variety of dimensions and structures. However, these materials were earlier restricted for use as anode materials for lithium ion batteries due to their cost and performance. With the development of nanotechnology, some modified and new forms of carbon fibers have emerged, which show good performance as anode materials. This paper reviews recent domestic and foreign research progress on fibrous carbon materials as anode materials. The electrochemical performance and prospective use of graphite fibers, carbon fibers and carbon nanofibers for this purpose are summarized. Research has ranged from non-graphitized to graphitized carbon fibers, from micron to nanometer diameter, and has focused on the parameters of their preparation to the design of their microstructure. Fibrous carbon materials are likely to be important alternatives for carbon anode materials in the future based on their high capacity, high rate capability, low cost and ease of industrialization. [New Carbon Materials 2015, 30(1): 1–11] [ABSTRACT FROM AUTHOR]

Natural microcrystalline graphite (MG), which shows highly graphitized structure and near-isotropic material properties, can be used as filler material in isotropic graphite preparation. The final properties of graphite artifacts are largely determined by the interaction between pitch and filler particles during kneading. To achieve a better understanding of the wetting mechanism of MG filler, wetting behavior of pitch on substrates with different crystal structures was studied by measuring their contact angles. The results showed that both crystalline orientation and degree of graphitization of substrates could significantly influence the pitch wettability. Edge planes of graphite surface showed better wetting capacity than basal planes. And cokes obtained at very high temperature with highly graphitized structure tended to prevent pitch from wetting. Further wetting test showed that MG substrate was totally wetted by pitch drop, and its wetting time was shorter than coke. The wetting behavior of MG was related to its unique crystalline structure and surface morphology, and beneficial to the mechanical strength of MG-based isotropic graphite. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman scattering (SERS) is a sensitive, fast, and nondestructive technology to detect trace amounts of molecules. The development of ultrasensitive and environmentally stable noble‐metal‐free SERS substrates is crucial for practical applications but still very challenging. In this contribution, an in situ substitutional doping strategy to synthesize Re‐doped WSe2 (Re‐WSe2) with different doping levels is reported. By increasing the Re content to ≈50 at%, the Re‐WSe2 alloy inherits the 1T″ phase of the ReSe2 lattice. Furthermore, Nb atoms are doped into the 1T″ Re‐WSe2 alloy to further modulate its electronic structure. The as synthesized 1T″ Nb, Re‐WSe2 demonstrates a femtomolar‐level molecular sensing capability with a detectable concentration of 5 × 10–15m and the corresponding enhancement factor is 2.0 × 109, which is superior to that of most non‐noble‐metal SERS substrates and comparable or even superior to that of noble‐metal substrates to the best of the authors' knowledge. More importantly, the as‐synthesized 1T″ Nb, Re‐WSe2 exhibits excellent air‐stability over a long term (≈6 months) and selective detection capability in the mixed molecular solution, which are essential for their practical applications. The work provides a new strategy for the rational design of noble‐metal‐free SERS substrates to achieve ultrasensitive molecular sensing. [ABSTRACT FROM AUTHOR]