Influence of Oxygen Concentration on Synthesis of Carbon Nano-Structures in Inverse Jet Diffusion Flames of Mixed Fuels

• Main Authors: Wen-Chang Chen, 陳文章
• Other Authors: 侯順雄
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/4d4kng

碩士 === 崑山科技大學 === 機械工程研究所 === 96 === The influence of volumetric oxygen concentration on the formation and growth of carbon nano-structures including carbon nanotubes (CNTs) and carbon nanocapsules in inverse co-flowing diffusion flames was experimentally studied. We employed a sampling Ni grid as the catalytic metal substrate for the carbon nano-structures growth. The sampling time of the substrate inside the flame was kept at 120 sec. The SEM and TEM images showed that carbon nano-structures deposited on the substrates were only CNTs for a lower oxygen concentration 25%. However, for higher oxygen concentrations30%, 35%, and 40%, besides curved CNTs, carbon nanocapsules were also synthesized. Note that both the growth range and yield of carbon nano-structures were increased with increasing oxygen concentration. Additionally, the sampling positions on or near the yellow flame front had a greater carbon nano-structures harvest than those far from the flame front.