SYNTHESIS OF WELL CRYSTALLIZED BORON-CARBON FILAMENT BY CHEMICAL-VAPOR-DEPOSITION USING A NICKEL-CATALYST

Thin filamentous boron-substituted carbon, BCx, has been synthesized b y chemical vapor deposition using a nickel catalyst at 800 degrees-110 0 degrees C from benzene, boron trichloride and hydrogen. The C/B rati os of the deposited products increased from 4 to 58 with increase in t he deposition temperature from 800 degrees to 1100 degrees C. BCx samp les also contained oxygen and hydrogen, the amount of which decreased with increasing deposition temperature and increased with increasing d uration of the deposition. The crystallinity of BCx samples was signif icantly improved by the use of a nickel catalyst. The d(002) values we re in the range of 0.336-0.338 nm smaller than 0.342 nm for a product prepared without catalyst, increasing with increasing duration of the reaction. XPS data suggest the existence of B-BC2, BC3 and B-O bonding s in BCx. (C) 1998 Elsevier Science Ltd. All rights reserved.