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Báo cáo hóa học: " A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4 over Mo2-Fe10/MgO Catalyst"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4 over Mo2-Fe10/MgO Catalyst | Nanoscale Res Lett 2009 4 574-577 DOI 10.1007 S11671-009-9284-Z NANO EXPRESS A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4 over Mo2-Fe10 MgO Catalyst Ouyang Yu Li Daoyong Cao Weiran Shi Shaohua Chen Li Received 15 September 2007 Accepted 19 February 2009 Published online 4 March 2009 to the authors 2009 Abstract A temperature window for the synthesis of single-walled carbon nanotubes by catalytic chemical vapor deposition of CH4 over Mo2-Fe10 MgO catalyst has been studied by Raman spectroscopy. The results showed that when the temperature is lower than 750 C there were few SWCNTs formed and when the temperature is higher than 950 C mass amorphous carbons were formed in the SWCNTs bundles due to the self-decomposition of CH4. The temperature window of SWCNTs efficient growth is between 800 and 950 C and the optimum growth temperature is about 900 C. These results were supported by transmission electron microscope images of samples formed under different temperatures. The temperature window is important for large-scale production of SWCNTs by catalytic chemical vapor deposition method. Keywords Single-walled carbon nanotubes Catalytic chemical vapor deposition Raman spectroscopy Introduction Since single-walled carbon nanotubes SWCNTs were discovered in 1993 1 they have generated significant research activities due to their particular microstructures unique properties and great potential applications in many fields. A single-walled nanotube can be described as a single layer of a graphite crystal that is rolled up into a seamless cylinder with both ends capped with hemispheres made of hexagonal and pentagonal carbon rings. With O. Yu El L. Daoyong C. Weiran S. Shaohua C. Li Lab for Nano-functional Materials Lin Yi Normal University Shandong 276005 China e-mail ouyangyu1976@tom.com 0 Springer remarkable properties SWCNTs can be explored to be used in novel applications like pressure sensors flow