2002 heterogeneous catalysis, catalysts

heterogeneous catalysis, catalystsH 2000

30 - 018Heterogeneous Single-Walled Carbon Nanotube (SWNT) CatalystDiscovery and Optimization. — Active catalysts for the growth ofSWNTs using the liquid-phase precursor approach are identified by high-throughput microarray techniques. After CVD, the catalyst arrays arequalitatively screened for yield via electron microscopy. Candidate catalystsare further characterized by confocal Raman spectroscopy. Compounds of thegeneral formula SixFeyAlaCob (x ≈ 1, y ≈ 1.5, a ≈ 2, b ≈ 1) give SWNTs ofvarying diameter distributions. The use of heterogeneous catalysts for CVD-based SWNT growth shows great promise for controlling different aspects ofSWNT synthesis through further catalyst engineering that will aid in large-scalenanodevice assembly. Films spun from these liquid-phase precursors could beuseful for large-scale patterning on microfabricated substrates. — (CHEN,BIN; PARKER II, GOLDWYN; HAN, JIE; MEYYAPPAN, M.; CASSELL,ALAN M.; Chem. Mater. 14 (2002) 4, 1891-1896; NASA Ames Res. Cent.,Moffett Field, CA 94035, USA; EN)

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