In situ CCVD synthesis of carbon nanotubes within zeolite crystal coated porous ceramic foam

Abstract

In this study, consolidated zeolite crystal coated porous ceramic foams containing a large quantity of carbon nanotubes (CNTs) within micro-metre sized pores were prepared. An alumina-silica porous ceramic body, having an average pore size of less than 100 μm, was produced by the direct foaming technique. Well-shaped zeolite crystals having an average size of 180 nm were synthesized and homogeneously coated on the porous ceramic body by an in situ process. An Fe-supported zeolite/ceramic matrix, which is used for CNT synthesis, was prepared using ion-exchange by immersing the zeolite-coated porous ceramic body into FeCl2 aqueous solution. The CNTs were synthesized by a catalytic chemical vapour deposition (CCVD) process for four different reaction times. Both acicular-shaped and randomly bundled networks of multi-walled carbon nanotubes (MWCNTs) were synthesized using these different reaction times. Moreover, the yield of CNTs produced showed a tendency to increase with increasing reaction time.