| In recent years, compound semiconductor of Boron carbon nitride (BCN) is normally considered as an important hard coating material system in industrial applications. Besides the band gap of the BCN can be adjusted for the industrial requirement by the different synthesis technology, which could improve the application in the optoelectronic devices fields. The various interesting nanostructures and novel optoelectronic properties have been realized. The Nanotube and films of BCN deposited on silicon substrate have been obtained by chemical vapor deposition and physical vapor deposition, respectively.Up to now, there are few reports on the formation of BCN on the other templates except silicon substrate. For example, the BCN was synthesized on the diamond film. Carbon fibers (CFs) have been widely applied in many fields for their outstanding electrical, thermal, and mechanical properties. The carbon fiber was also used as the special electrode materials due to the good conductor and high temperature resistance. For example, the electrochemical activity of boron- doped diamond grown on carbon fibers used as electrodes is better than that of diamond films. So synthesize BCN /carbon fibers composite material with porous configuration not only provided the character of BCN material but also the application of carbon fibers. Besides the new materials may be used as the carrier of micro or nano catalyst and its character of absorption waves can be exploited due to the porous configuration.BCN /carbon fibers with porous configuration were synthesized by hot filament chemical vapor deposition (HF-CVD). The B, N, C sources were from B(OCH3)3, N2 and carbon fiber (or CH4), respectively. The structure of the composite fiber is composed of the carbon fiber which is covered by the cylindrical BCN films with 5–10μm in thickness. The different reactant gases lead to the different surface morphology and the diameter of the composite. The FTIR spectral results of the composite fibers indicate that the elements of B, C, and N are chemically bonded with atomic-level BCN hybrid in the product. The resistance of the composite fibers is about 300Ωwhich is 10 times higher than that of the isolated raw carbon fibers (27.5Ω). These V-I results indicate that the different surface shape and diameter of the BCN layer lead to the different electrical properties. The composite fibers with porous configuration prepared in this work may be useful to exploit the application of BCN material.Besides,the diamond film of nitrogen and boron doped was synthesized by EA-CVD method. The gas sources were H2, CH4, N2 and B(OCH3)3 . The temperature was round 900℃,and the press was the 25 torr, the depositing time was 20-90h. The influence of nitrogen and boron doping on their growth characteristics was studied in this paper. Nitrogen concentration in the reacting gas directly affects the growth rate of the films. And the growth rate of the diamond films first increases and then decreases with the increase of the nitrogen flow rate. When the nitrogen flow rate is 0.5 and 3 sccm, the crystal faces are mainly (111) and (110) faces, whereas they are rough and the twins as well as secondary nucleation increase. As the nitrogen flow rate rises to 1.5 and 4.5 sccm, the morphology become"cauliflower-like", and (100) faces can be easily observed the"cauliflowers", and the grains are incompact. These results indicate that the quality of the diamond has been descended with the nitrogen concentration increasing. This can be further confirmed by the following results of Raman spectra. The results of Raman spectra show that the films exhibit good quality with relatively low concentration of non-diamond phase at different nitrogen flow rates. In addition, the results of Raman spectra and SEM show that the quality of the diamond films was descended when the nitrogen and boron doped together.
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