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Due to its suitable bandgap and excellent stability, 3C-SiC is being investigated as one of the promising candidates for photoelectrochemical (PEC) water oxidation. However, the limited surface activity and short carrier lifetime prevent 3C-SiC photoanodes from facilitating efficient PEC water splitting. To tackle these problems, this work proposes a plasma technique to control the crystal structure and optical characteristics of 3C-SiC. Nitrogen plasma induces carbon vacancies (Vc) and Si–N bonds, further leading to a narrower bandgap of 3C-SiC. The combination of Vc and N doping enhanced the light trapping capability of the electrode, thereby improving the efficiency of electron–hole pair separation and charge transfer, resulting in an accelerated water oxidation reaction, i.e., photocurrent density (2.50 mA cm−2 at 1.23 VRHE) increased by 7.6 times compared to that of pristine SiC. This work offers an effective strategy for regulating the electronic structure of SiC-based photoanodes by plasma treatment, which may be extended to other photoelectrodes for PEC application. [ABSTRACT FROM AUTHOR]

Controlling the isotropic and anisotropic graphene growth in a chemical vapor deposition (CVD) process is a critical aspect to understand the growth dynamics for synthesizing large-area single crystals. Here, we reveal the effect of gas flow and controllability on isotropic and anisotropic graphene growth using a solid carbon source-based atmospheric pressure CVD method. It was found that the growth rate of round-shaped crystals (isotropic growth) was much higher than that of hexagonal crystals (anisotropic growth). The average growth speed increased from 0.276 μm min−1 to 1.89 μm min−1 by switching from hexagonal to circular domain growth in the CVD process. It was also found that there was no significant difference in the quality of graphene crystals when switching the growth from anisotropic to isotropic. Understanding the growth rate of round and hexagonal-shaped crystals can be critical to achieve faster growth of large single crystals. Again, the mixed edge structures (armchair and zigzag) in round-shaped graphene crystals without a fixed orientation unlike hexagonal crystals provide a better chance of seamless merging. Our findings can be significant in understanding the formation of isotropic and anisotropic graphene domains, their growth rate and quality for synthesizing large-area single crystals. [ABSTRACT FROM AUTHOR]

Most of the chemical vapor deposition (CVD) systems used for hexagonal boron nitride (h-BN) growth employ pyrolytic decomposition of a precursor molecule, such as ammonia borane (AB), at a temperature close to its melting point. So the control of its partial pressure is essential for high quality crystal growth. Here, we report on the edge controlled growth of a h-BN single crystal larger than 25 μm in edge length on purchased Cu foils. The key was the controlled supply of borazine gas generated by the decomposition of AB, and the stepwise decomposition of AB was found to be essential for the growth of regular h-BN crystals. The h-BN growth was mostly governed by the position of the nucleation point rather than Cu orientation as confirmed by electron back-scattered diffraction (EBSD) analysis. It was also demonstrated that the variation in temperature during the growth and cooling processes induced wrinkles larger than 20 nm due to the thermal straining of the Cu surface and a negative expansion coefficient of h-BN. These results provide a detailed understanding of h-BN growth, which will be applicable to other 2D materials. [ABSTRACT FROM AUTHOR]

Graphene-sheet fiber, a novel structure of graphitic carbon, grew from coffee grounds under the condition of microwave plasma irradiation. The resulting fiber consisted of only few-layer graphene without a hollow structure inside while possessing a large amount of graphene edges and high conductivity. Due to these advantages, graphene-sheet fibers may find applications in electrochemical energy conversion and storage. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWNTs) have been used successfully to fabricate highly transparent and flexible field emission displays (FEDs). Field emission measurements indicated that SWNTs films have great potential to work as building blocks for next generation transparent and flexible FEDs. [ABSTRACT FROM AUTHOR]

We demonstrate the formation of a photoinduced charge transfer composite with graphene oxide (GO) and ferrocene (Fc) molecules. Derived insulating GO was partially reduced to improve the conductivity and modified with the Fc molecules. Transmission electron microscopy (TEM), elemental mapping, X-ray photoelectron and UV-visible spectroscopy studies confirm that the Fc molecules were well grafted to the surface of a GO sheet. Photoresponsivity of the prepared GO-Fc composite was investigated by fabricating a metal/GO-Fc/metal device. The fabricated device shows enhanced current density under light illumination, suggesting a photo-induced charge transfer process in the developed GO-Fc composite.

The organic-organic self-assembly method with Resorcinol (R)/Formaldehyde (F) and Pluronic F127 has been employed to synthesize mesoporous carbon (MC). The pore diameter of the MC has been tuned from 7 to 12.5 nm by changing the molar ratio of carbon sources to surfactant and polymerization time., (This journal is © The Royal Society of Chemistry 2011)

Direct growth of aligned metal composite carbon nanofibers (MCNFs) was achieved by a highly reproducible room temperature growth process on cost effective electrically conductive copper (Cu) substrate without any catalyst. The direct fabrication of MCNFs on electrically conductive substrate might offer new perspectives in the field of field emission displays (FEDs)., (© The Royal Society of Chemistry 2011)