Presentation Information
[9a-E215-5]Identifying governing factors of yield and diameter in floating-catalyst synthesis of carbon nanotubes
〇Keigo Otsuka1, Ryuji Fujiwara1, Shigeo Maruyama1 (1.The Univ. of Tokyo)
Keywords:
floating-catalyst sythesis,carbon nanotubes,diameter control
In floating-catalyst CVD of carbon nanotubes (CNTs), the temperature and carbon activity vary in a complex manner along the furnace, so the mechanisms that determine the structure of individual tubes and the overall yield remain unclear. Here, we rapidly screened the synthesis parameters and carried out comprehensive experiments within a short time. We found that both the yield and the diameter are governed by the carbon chemical potential at the catalyst (μcat); in particular, adding CO2 increases the mean diameter likely by shifting the nucleation position to a region where the catalyst particles are larger. Aiming at a comprehensive understanding, we develop a kinetic model that describes the catalyst from nucleation through steady-state elongation to deactivation in terms of temperature and μcat.