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Dispersion of carbon black (CB) powder in CB/polymer composites considerably influences their mechanical properties, electrical conductivity, and thermal conductance. In this study, with the aim to improve the dispersion of CB powder in the CB/polymer composites, CB was treated with oxygen and nitrogen plasma generated by radio frequency-plasma enhanced chemical vapor deposition (RF-PECVD), and then, dispersed in a poly(vinylidene fluoride-co-hexafluoropropene) (PVDF-HFP) solution. The solution was then subjected to electrospinning, leading to the formation of a nanofiber mat. The dispersion states of plasma treated CBs have been characterized using scanning electron microscopy and Fourier-transform infrared spectroscopy. A stress–strain curve was used to investigate the influence of dispersion on the mechanical properties of CB/polymer composites.

Nanocrystalline diamond (NCD) is exceptionally useful for a variety of applications and is of significant interest to researchers in technological and scientific fields due to its excellent mechanical and chemical properties, such as its hardness and high thermal conductivity. We have modified a microwave plasma chemical vapor deposition (MPCVD; Astex Inc.) system with a slot antenna designed for surface wave plasma (SWP) and successfully fabricated high quality thin NCD film. This SWP-CVD process fabricates high quality diamond film at 300 °C, while a normal MPCVD process requires the temperature of the substrate to be above 800 °C. We studied the fabricated NCD samples in detail, measuring their surface morphology by field emission scanning electron microscopy (FESEM); their structural-chemical properties by Raman spectroscopy; and their surface roughness by atomic force microscopy (AFM).

Because of its stable crystal structure, a boron-doped diamond (BDD) has been attracting great attention as a promising material for a next-generation electrode. For instance, the BDD is a wellknown candidate to be exploited as an electrode for the ozone generation with its longer life-time. In this study, we have evaluated ozone-generating characteristics of the BDD electrodes related to the doping concentration of boron. In the experiment, morphology of surface was observing by scanning electron microscopy (SEM) and structural-chemical properties of the synthesized diamond layers were characterized by Raman spectroscopy. Conductivity, carrier concentration, and Hall mobility were determined by a Sheet resistance measurement and Hall effect measurement performed based on the van der Pauw method. The ozone concentration in the water was measured using an ozone colorimeter with DPD reagent.

In this research, catalyst-free vertically aligned boron doped carbon nanowalls films were fabricated on silicon (100) substrates by MPECVD using feeding gases CH4, H2 and B2H6 (diluted with H2 to 5% vol) as precursors. The substrates were pre-seeded with nanodiamond colloid. The fabricated CNWs films were characterized by Scanning Electron Microscopy (SEM) and Raman Spectroscopy. The data obtained from SEM confirms that the CNWs films have different density and wall thickness. From Raman spectrum, a G peak around 1588 cm(-1) and a D band peak at 1362 cm(-1) were observed, which indicates a successful fabrication of CNWs films. The EDX spectrum of boron doped CNWs film shows the existence of boron and carbon. Furthermore, field emission properties of boron doped carbon nanowalls films were measured and field enhancement factor was calculated using Fowler-Nordheim plot. The result indicates that boron doped CNWs films could be potential electron emitting materials.

Multi wall carbon nanotubes (MWCNTs) and diamond are renowned as superlative material due to their relatively high thermal conductivity and hardness while comparing with any bulk materials. In this research, polyacrylonitrile (PAN) solution incorporated with MWCNTs at an alteration of mass fractions (0 wt%, 0.6 wt%, 1 wt%, 2 wt%) were fabricated via electrospinning under optimized parameters. Dried composite nanofibers were stabilized and carbonized, after which water base polytrafluorethylene (PTFE) mixed with nano diamond powder solution was spin coated on them. Scanning electron microscopy, Raman spectroscopy, X-ray scattering and Laserflash thermal conductivity were used to characterize the composite nanofiber sheets. The result shows that the thermal conductivity increased to 4.825 W/m K from 2.061 W/mK. The improvement of thermal conductivities is suggesting the incorporation of MWCNTs.

High density plasma etching of ultrananocrystalline diamond (UNCD) films wasperformed in O2 and O2/Ar inductively coupled plasma (ICP) discharges. The O2/Ar ICP discharges produced higher etch rates due to enhanced physical component of the etching, and a maximum etch rate of -280 nm/min was obtained in 10 sccm O2/5 sccm Ar discharges. Very high etch selectivities up to -140:1 were obtained for the UNCD over Al mask layer. Anisotropic pattern transfer with a vertical sidewall profile was achieved in the 10 sccm O2/5 sccm Ar discharges at a relatively low source power (300 W) and a moderate rf chuck power (200 W).

In this study, we report the synthesis and characterization of novel hybrid nanocoating based on carbon nanotubes (CNTs) on anodized aluminum surfaces (AAO). The hybrid nanocoating was deposited by number of methods which include spray coating, spin coating and dip coating. The bonding of nanocoating with metal surface is an important parameter for successful modification of the metal surfaces. The improved adhesion of nanocoating on metal surfaces could be attributed to chemical bonding of sol-gel nanocoating with anodized surfaces. The nanocoated anodized aluminum surfaces showed superior adhesion and excellent anticorrosive properties. The nanocoated panels showed enhanced galvanic protection comparable to 80% of titanium metal as determined by galvanic corrosion measurements. It also showed higher thermal conductivities than stainless steel and bare anodized surfaces.

Novel (Ba1_xEu(x))9Y2Si6O24 green phosphors were successfully prepared by a solid-state reaction method. The prepared (Ba1_xEu(x))9Y2Si6O24 green phosphors showed a single intense broadband emission in a range from 502 to 510 nm. The effects of the Eu2+ doping concentration on the optical properties were discussed under consideration of concentration quenching. The experimental results clearly indicates that the prepared (Ba1_xEu(x))9Y2Si6O24 green phosphors have great potentials as a down-conversion green phosphor for white light emitting diodes (LEDs) utilizing blue LEDs as the primary light source.