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The challenge in developing a protection barrier from corrosion is to develop an economical yet efficient method for the coating material. Graphene has been deemed to be an ideal coating material for anti‐corrosion, yet its long‐term performance is disappointing due to galvanic corrosion. In an effort to address issues associated with graphene materials, we have developed an amorphous nitrogen doped carbon (a‐CN) film material exhibiting remarkable anti‐corrosion properties. The anti‐corrosion performance of this material appears to be superior to graphene because of its strong ion transportation resistance. [ABSTRACT FROM AUTHOR]

A bottom‐up method to fabricate uniformly dispersed graphene quantum dots (GQDs) by atmospheric pressure CVD on copper substrates is reported. The size distribution of the GQDs can be controlled by carefully tuning the CVD growth parameters. Additionally, the GQDs can easily be transferred to other large‐scale substrates and the fabrication process is relatively simple and convenient. The GQDs deposited on transparent substrates show well‐known excitation‐dependent photoluminescence behavior. [ABSTRACT FROM AUTHOR]

Photoinduced molecular desorption from solid surfaces will modify the electrical transporting properties of matter and result in significant change in resistance. The UV induced resistive response of graphene films prepared by chemical vapor deposition was investigated. The resistance of graphene increased exponentially upon UV irradiation and decreased also in an exponential form when the UV light was turned off. Both processes exhibited large time constants of hundreds of seconds. UV-induced molecular desorption mechanisms for graphene, carbon nanotubes, and reduced graphene oxides were compared and discussed. [ABSTRACT FROM AUTHOR]

Abstract: Fe-filled thin-walled carbon nanotubes (CNTs) were synthesized by chemical vapor deposition. Dichlorobenzene/ferrocene solution was used both for carbon source as well as Fe source. Chlorine-contained precursor is in favor of the fabrication of thin-walled CNTs. The productive HCl in the reaction ambient could etch the CNT wall and growth front-end. Auger electron spectroscopy (AES) results indicated that the Cl atoms were almost entirely carried away by the carrier gas. Thermogravimetric analysis (TGA) showed that the filling rate of the Fe-filled thin-walled CNTs could be adjusted by controlling the flow rate of H2. [Copyright &y& Elsevier]

A new form of hybrid carbon-based thin film was prepared viaa pyridine chemical vapour deposition method. The as-obtained films consist of agglomerated flowerlike graphene nanowhiskers embedded in a uniform matrix of amorphous carbon. Schottky solar cells made from the hybrid films and n-type silicon show conversion efficiencies of ∼1% under AM 1.5 illumination. [ABSTRACT FROM AUTHOR]

Graphene woven fabric (GWF) prepared from chemical vapor deposition was used as smart self-sensing element to assemble piezoresistor through directly transferring onto the flexible substrate poly(dimethylsiloxane) (PDMS) with the deposited Ti/Au electrodes. A rational strategy was proposed to fabricate flexible touch sensors easily and effectively with the full usage of the mechanical and electrical properties of GWF, whose resistance is highly sensitive to macro-deformation or micro-defect. Compared to commercial and traditional touch sensing, the GWF-on-PDMS piezoresistor is structurally flexible that is demanded under special conditions and meanwhile makes the piezoresistor to have excellent durability. [ABSTRACT FROM AUTHOR]

We demonstrate an improved low-pressure chemical vapor deposition method to fabricate hexagonal boron nitride (h-BN) domains of a few layers (one–four layers) from ammonia borane by adding a small quartz tube to stabilize the gas flow over the copper substrate and reducing the growing rate of h-BN. The h-BN grows freely and spontaneously to form triangular domains on the Cu (100) plane. The triangular domains are prone to be parallel to each other on the copper substrate. The h-BN domains grow by extending in the normal direction of the triangle and form a large thin film by joining together. Both the size and coverage rate on Cu foils are well controlled by tuning the amount of ammonia borane. [ABSTRACT FROM AUTHOR]

Abstract: The recyclability of carbon nanotube (CNT) sponges in terms of oil absorption was studied. The sorption capacities of these sponges are greater than 100gg–1 for many organics and oils with viscosities of 3–200cP, and they maintain sorption capacities of 20–40gg–1 after 10 cycles of absorption. About 98% of absorbed oil can be recovered by squeezing or converted to heat by directly burning the oil within the sponges. The sorption process has been described by a second-order kinetic model. The results demonstrate that CNT sponges are promising oil sorbents with good recyclability. [Copyright &y& Elsevier]

Abstract: Carbon nanotube (CNT) arrays doped with nitrogen were synthesized using chemical vapor deposition by pyrolysis of xylene/pyridine and ferrocene with a modified precursor feeding technique. The system produced a gradient of nitrogen concentration that modified the CNTs from a hollow cylinder to a bamboo-shaped structure which contains a series of compartments whose lengths are gradually reduced as the nitrogen concentration increases. [Copyright &y& Elsevier]

Abstract: Silicon nanowire (SiNW) arrays were fabricated on silicon wafers by the metal-assisted chemical etching method. Varied average diameters of SiNW arrays were realized through further treatment in a mixed agent of HF and HNO3 of certain concentrations. After the treatment, there were more than 93% SiNWs with diameters smaller than 100nm. The tip of each SiNW was subsequently wrapped with multi-walled carbon nanotubes (MWCNTs) with chemical vapor deposition method. The as-fabricated MWCNT/SiNW arrays were fabricated into electric field emitters, with turn-on field of 2.0V/μm (current density: 10μA/cm2), much lower than that of SiNW array (5.0V/μm). The turn-on electric field of MWCNT/SiNW array decreased with the decreasing of the average diameter of SiNWs, indicating the performance of the field emission is relative to the morphology of SiNWs. As the SiNW array is uniform in height and easy to fabricate, the MWCNT/SiNW array shows potential applications in flat electric display. [Copyright &y& Elsevier]

Abstract: The temperature effect on synthesizing different carbon nanostructures in the range of 820−1020°C by sulfur-assisted chemical vapor deposition is investigated. When the growth temperature is no more than 900°C (e.g. 820, 860, and 900°C), carbon onions can be obtained, accompanying with some fishbone-like carbon nanofibers (CNFs), graphite sheet and carbon nanotubes (CNTs). When the growth temperature is increased to 940°C or above (e.g. 980 and 1020°C), the products are mainly CNTs. Furthermore, by comparing the nitrogen adsorption–desorption results of samples obtained with and without sulfur addition at each temperature, it is found that the specific surface area (SSA) of products can be remarkably enlarged after introducing small amount of sulfur during growth. This is favorable to their applications in areas like electrodes of supercapacitors, adsorbents, catalyst supports, and so on. [ABSTRACT FROM AUTHOR]

Abstract: Two different growth modes of carbon nanotubes (CNTs) are identified in ethylene chemical vapour deposition (CVD) using SiO2 as support. With a series of electron microscopy observations, we have found that small-diameter nanotubes favor a root-growth mechanism on nanoporous SiO2 support, while nanotubes with larger diameters prefer a tip-growth. The dependence of growth mode on tube diameter is explained in terms of the porosity of the support and the size distribution of the catalyst. Our results provide clues to control growth of CNTs and obtain well-organized nanotube structures. [Copyright &y& Elsevier]

Abstract: We present a strategy to control the chirality of single-walled carbon nanotubes synthesized by chemical vapor deposition (CVD) over crystalline catalyst nanoparticles. Atomic-resolution imaging of nucleation points makes it possible to explore the structural correlation between the catalysts and the corresponding nanotubes. The formation of nanotubes with specific chirality could be associated with the angle of the step edge on (111) plane of the particle with respect to the growth direction of nanotubes. The result shows the potential in promoting some experimental advances in synthesis of nanotubes with the desired structure. [Copyright &y& Elsevier]

Abstract: In this paper, double-walled carbon nanotube (DWNT) bundles can be transformed into multi-walled carbon nanotubes (MWNTs) by electric current treatment in vacuum. The morphology of the transformed MWNTs shows an obvious dependence on power density of the current, which changes from partly transformed MWNTs to collapse MWNTs with the increase of power density. The process of this structural transformation follows the tendency of forming more stable structures, and can be ascribed to the sequential coalescence of DWNTs inside the bundles. [Copyright &y& Elsevier]

Abstract: This study shows that S concentration in the Fe catalyst plays an important role in controlling the number of graphene layers during carbon nanotube (CNT) growth via chemical vapor deposition. Using different S concentrations, we have grown thin carbon nanotubes with from 1 to 5 layers. Single-walled carbon nanotubes growing from the active surface of an FeS–Fe eutectic were observed. A growth model basing on the HRTEM characterization and thermodynamic analysis is suggested in which the CNT nucleates and grows on the active surface area of the catalyst where S accumulates in the form of an FeS–Fe eutectic, and the S distribution on the catalyst particle surface determines the number of CNT layers. [Copyright &y& Elsevier]