Morphology of Carbon Nanotubes Prepared on Alumina Supported Iron Catalyst by Mechanochemical Treatment

摘要

Morphologies of carbon nanotubes(CNTs) grown on the Fe(NO_3)_3-Al(OH)_3 mixtures by thermal CVD with C_2H_2 as the carbon source are discussed in this paper. Fe(NO_3)_3-Al(OH)_3 mixtures prepared by impregnation method have been mechanochemically treated by the high energy grinding process using a mixer mill. CNTs were grown by thermal CVD under C_2H_2 and H_2 gases at 700°C on as-prepared unground and ground mixtures. The unground and ground samples of Fe(NO_3)_3-Al(OH)_3 mixtures were examined by XRD and SEM at different grinding times. CNTs grown on unground and ground mixtures were characterized by SEM and TEM studies. The CNTs grown on ground mixtures were found to have more uniform diameter than those on unground mixture. In addition to this, morphological changes of carbon nanotubes grown on unground and ground mixtures show that the modification of catalyst by mechanochemical treatment can be used as a tool for CNT growth control.