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To enhance the fracture toughness of silicon carbide (SiC) ceramics and prevent the generation of cracks and chippings in the SiC ceramics during machining process, carbon nanofibres ( CNFs) were compounded with SiC. The densification and microstructure development of the CNFs/SiC composites pressureless sintered in Ar atmosphere were investigated. The fracture toughness of SiC ceramics was enhanced by the addition of 1-3 wt% CNFs, which resulted from the pullout and/or bridging effect of CNFs bonded much more closely with SiC. The addition of 3 wt% CNFs prevented the chippings from generating in the composite during precision machining process. [ABSTRACT FROM AUTHOR]

In article number 2100205, Morelos-Gomez, Terrones and Endo explore how, with the aid of tools from data science, carbon nanomaterials research and development can accelerate in three key experimental areas: synthesis, characterization, and applications. B Data Science Applied to Carbon Materials b Carbon materials have been the main subject for two Nobel prizes; they exhibit excellent physical and chemical properties that have been used in diverse applications. Data Science Applied to Carbon Materials: Synthesis, Characterization, and Applications (Adv. [Extracted from the article]

Carbon nanofibers (CNFs) were soaked in 1.5 simulated body fluid (1.5 SBF) in which inorganic ion concentrations are 1.5 times as high as those in the standard SBF. The influence of the CNFs content in 1.5 SBF and pretreatment of the CNFs on the biomimetical deposition of apatite were investigated. The spherical bone-like apatite particles were deposited on the pristine CNFs soaked in 1.5 SBF. Amount of deposited apatite per a unit of CNFs increased with a decrease in the CNFs content in 1.5 SBF, and it decreased markedly when the CNFs were pretreated with concentrated sulfuric acid/nitric acid (3 : 1 v/v) mixture for longer periods. Such results suggest that too many nucleation sites of apatite, which were functional groups, such as carboxyl and hydroxyl groups, existed on the CNFs in the 1.5 SBF, and most embryos formed on the sites could not grow to critical nuclei and furthermore did not grow to apatite. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanofiber–copper composite films with different types of nanofibers were fabricated by an electrodeposition process. Four types of carbon nanofibers, vapor-grown carbon nanofibers without heat treatment, vapor-grown carbon nanofibers with heat treatment, vapor-grown carbon nanofibers with smaller diameters, and vapor-grown carbon nanofibers with a cup-stacked nanostructure were used. The carbon nanofibers were homogeneously dispersed in sulfate copper plating baths in the presence of polyacrylic acid. Electrodeposition was carried out under galvanostatic conditions using these copper plating baths. The deposition resulted in electrodeposited copper films containing the carbon nanofibers distributed homogeneously. The surface morphology of the carbon nanofiber–copper composite films was observed to be affected by the type of carbon nanofiber used. [Copyright &y& Elsevier]

Nickel-coated carbon nanofibers have been prepared by an electroless deposition process. The carbon nanofibers were pre-treated prior to the nickel electroless deposition. Polyacrylic acid was used to disperse carbon nanofibers in the pre-treatment solutions. The carbon nanofibers were coated homogeneously with nickel by the electroless deposition process using an electroplating bath containing sodium hypophosphite as a reducing agent. The process resulted in a powdery-nickel-coated carbon nanofiber material. [Copyright &y& Elsevier]

Abstract: Nickel–carbon nanofiber composites were synthesized by means of pulse-reverse (PR) electrodeposition technique from a standard Watts nickel plating bath using a cationic polymer as the dispersing agent of nanofibers. The obtained composites were characterized by electron probe X-ray microanalyzer, field-emission scanning electron microscope and X-ray diffractometer to demonstrate their microstructures. Results clearly showed that the composites were formed as the continuous films filled by a large amount of individual Ni-coated nanofibers with a closely packed arrangement. The PR electrodeposition enhanced the carbon nanofiber concentration compared to the DC electrodeposition in the nickel–carbon nanofiber composites. The morphological features and the composition of composites exhibited controllable characters by selectively modulating the PR electrodeposition parameters. [Copyright &y& Elsevier]

• Aerogel developed from CNF anchored with transition metal divalent ions enhanced by CNT. • Efficiently absorb ammonia, trimethylamine, hydrogen sulfide, and methyl mercaptan. • The hybrid aerogel showed steady performance in a wide range of temperatures from 0 °C to 40 °C. • The first aerogel type deodorizer material ever reported in air decontamination. • Aerogel is eco-friendly and economic, suitable for domestic and industrial uses. A novel deodorizer that is capable of selectively eliminating the odorous chemicals, such as ammonia, trimethylamine, hydrogen sulfide and methyl mercaptan, is described. The deodorizer is a nanostructured aerogel by nature, consisting of 2,2-6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized cellulose nanofibrils (CNF), transition metal divalent cations (M2+), and multi-walled carbon nanotubes (CNT) as the constitutive elements. CNF are firstly mixed with M2+ (M2+, in this paper, typifies Ni2+, Co2+ and Cu2+) to form CNF-M2+ complexes, monodispersed CNT is then mixed to prepare CNT/CNF-M2+ waterborne slurries; CNT/CNF-M2+ hybridized aerogels are finally obtained via freezing-drying of the CNT/CNF-M2+ waterborne slurries. The CNT/CNF-M2+ aerogels are a foam-like structure consisting of CNF and CNT as backbones and M2+ as linkers. The aerogels show higher capabilities (in comparison with activated carbon) for selectively adsorbing ammonia, trimethylamine, hydrogen sulfide and methyl mercaptan. Computing simulations suggest a theoretical conclusion that the odorous chemicals are absorbed in a preferring manner of bimolecular absorptions via the M2+ moieties. The CNT/CNF-M2+ hybridized aerogels are lightweight, eco-friendly, and easy to produce in industrial scales. Our new finding, as is described in this paper, demonstrates potential applications of the TEMPO-oxidized CNF to the field of deodorizations. [ABSTRACT FROM AUTHOR]

Pyrene crystals were grown on carbon nanofibers (CNFs) by dispersing pyrene polycrystals and CNFs in water during ultrasonic irradiation, and they were characterized by scanning electron microscopy, X-ray diffractometry (XRD) and spectroscopy. The XRD measurements indicated that the orientation and size of the pyrene crystals on the CNF aggregates were different from that of the added pyrene polycrystals. Based on the spectroscopic properties of the pyrene crystals on the CNFs, the pyrene crystals on the CNF aggregates and on the individual CNFs were determined to be polycrystals and single crystals, respectively. These results indicate that pyrene crystals are produced on the CNFs by recrystallization of the added pyrene polycrystals and their crystal states depend on the aggregation state of the CNFs. [Copyright &y& Elsevier]

Abstract: Acidic functional groups produced on the surface of acid-treated carbon nanofibers (CNFs) were characterized by fluorescence measurements using 1-aminopyrene (1-AP) as an in situ probe molecule. The 1-AP molecules only slightly interacted with the untreated CNF surface, whereas the 1-AP cation-like bands were observed on the HNO3-treated and HNO3/H2SO4 treated CNF surfaces. These results indicate that 1-AP was tightly immobilized by the hydrogen bonding interaction between its amino group and the Brönsted-acidic groups on the CNF surface. A stronger acid treatment (with HNO3/H2SO4 mixture) caused the chemical modification to generate higher amounts of the acidic functional groups on the CNF surface. [Copyright &y& Elsevier]

Aqueous dispersion consisting of 2,2,6,6-tegramethylpyperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TEMPO-CNFs), dodecyltrimethylammonium chloride (DTMACl), and diethylene glycol (DEG) was oven-dried at 40 °C for 1 d to prepare a dried product. The soft and bulky TEMPO-CNF/DTMACl/DEG material was added to a carboxy group-containing nitrile-butadiene rubber (XNBR) followed by removal of all the DEG molecules by vacuum drying at 80 °C for 8 h. The mixture was then subjected to kneading with high shear forces using a two-roll mill at 20–30 °C (i.e., elastic kneading), followed by pressing at 170 °C for 20 min to prepare cross-linked XNBR composite sheets consisting of TEMPO-CNF and DTMACl. The XNBR composite sheet containing 9.9 vol% TEMPO-CNF had an average tensile strength, storage modulus at 23 °C, work of fracture, and elongation at break of 19 MPa, 47 MPa, 2.7 MJ/m3, and 230%, respectively, whereas those of the reference cross-linked XNBR sheet were 11 MPa, 11 MPa, 0.9 MJ/m3, and 220%, respectively. Scanning transmission electron microscopy observation revealed unique fibrillated and cluster-like structures of the TEMPO-CNF were likely responsible for the excellent mechanical and thermal properties. The proposed process is industrially viable for conventional kneading processes to prepare composite rubber sheets with good mechanical and thermal properties. [Display omitted] [ABSTRACT FROM AUTHOR]