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Due to the excellent oxidation and hot corrosion resistance and matched thermal expansion coefficient to normal alloys, Cr2AlC has potential applications as high-temperature protective coating. In the present work, the preparation of Cr2AlC coating has been achieved through cathodic arc deposition method combined with heat post-treatment. It was found that the coating, deposited from Cr2AlC compound target in the unintentional heating condition, was amorphous. After annealing at 620 degrees C in Ar for 20 h, the amorphous Cr-Al-C coating happened to crystallize and transformed to crystalline Cr2AlC as the major phase. It is obvious that the formation temperature of Cr2AlC was decreased from about 1050 degrees C for sintered bulk to around 620 degrees C for the as-deposited coating, resulting from the homogeneous mixture of the Cr, Al and C at atomic level in the Cr-Al-C coating. Apart from crystalline Cr2AlC, the annealed coating also contained AlCr2 and little Cr7C3. AlCr2 formed due to the loss of C during deposition, and little Cr7C3 always existed in the sintered Cr2AlC compound target as impurity phase. (C) 2012 Elsevier B. V. All rights reserved.

Ferroelectric copolymer thin films P(VDF-TrFE) are used as a ferroelectric cathode for investigation of their electron emission properties. This ferroelectric copolymer films with different thicknesses are deposited by spin-coating method, and then the annealing process is carried out to improve the crystallinities of as-deposited copolymer films. The measurement results of ferroelectric electron emission showed that the copolymer P(VDF-TrFE) films had a desired ferroelectric electron emission ability excited at low-voltage pulse, and its peak emission current can reach to be ∼1.3 μA when the pulse voltage is 280 V. In addition, the effect of film thickness on electron emission property and emission stability of copolymer thin film P(VDF-TrFE) are discussed.

Heavily boron-doped diamond films are synthesized by the hot-filament chemical vapor deposition method under the gas mixtures of H2, CH4 and trimethyl borate. The measurement results of scanning electron microscopy, Raman spectroscopy, X-ray diffractometer and electrical properties showed the morphologies, microstructures, carrier concentration and superconducting transition temperature for as-grown diamond films were dependent on the change of growth pressure, and specially its carrier concentrations could be adjusted from 1019 to 1021 cm−3 by increasing growth pressures from 2.5 to 5 kPa. And further, the effects of growth pressure on the film microstructural property and the doping level dependence of the superconducting transition temperature were discussed.

Highly (0 0 2)-oriented AlN film was deposited on n-type (1 0 0)-oriented silicon substrates by the radio frequency magnetron sputtering method. An individual AlN cone with high aspect ratio was fabricated by the focused ion-beam (FIB) etching process in the surface of an as-formed AlN film. This etching method can easily control the tip radius and height to obtain AlN cones with different aspect ratios. The field-emission property of the individual AlN cone was measured in a scanning electron microscopy system equipped with a movable probe as the anode above the AlN tip. The results indicated that the as-formed single AlN cone with high aspect ratio possessed good field-emission ability although it only had a tiny emission area. Compared with a single Si tip fabricated by the same method, a single AlN cone exhibits better field-emission ability, and hence, has great potential as a promising candidate of point electron source for application in vacuum electronic devices.

A stable superhydrophobic surface was fabricated by solidifying poly(epoxy-terminated polydimethylsiloxane- co -bisphenol A) [P(ETPDMS- co -BPA)] copolymer on a rough substrate. The low surface energy of the copolymer and the geometric structure at micrometer scale of the surface contribute to the superhydrophobic property. The as-prepared surface shows stable superhydrophobicity over a wide pH range (1–14) and the wettability is excellent stable to heating, water, corrosive solution and organic solvent treatments. The procedure is simple and time-saving as well as utilizing non-fluorine-containing compounds.

Effect of annealing on the field emission properties of diamond-like carbon (DLC) films deposited by high power excime laser technique was studied. Raman spectrometry and X-ray photoelectron spectrometry (XPS) were used to determine the chemical bonding structural change of the annealed DLC films. It was found that the annealing transformed gradually DLC films into a graphitic structure as annealing temperature was increased to more than 600 degrees C, simultaneously field emission properties of DLC films were enhanced markedly. Graphitization of DLC films induced by annealing caused the formation of a large fraction of sp(2) C in the DLC films, which played an important role in the enhancement of field emission properties for DLC films. Rich sp(2) C cluster acted as a conduction part in the films could increase the conductivity of DLC films and lower the effective work function of DLC films, consequently improve field emission properties of DLC films. (c) 2005 Elsevier B.V. All rights reserved.