Vertically Aligned Carbon Nanotubes Grown from Langmuir–Blodgett Films with Nano Alloy Particles

In this study, we attempted to grow vertically aligned carbon nanotubes (VA-CNTs) from Langmuir–Blodgett (LB) films with accumulated nanoparticles and compare and evaluate the results with VA-CNTs grown from LB films with accumulated AlFe2O4 nanoparticles in the addition to CoFe2O4 and Fe3O4 nanoparticles. CVD was performed on the accumulated LB films under the following conditions. As a result, VA-CNTs grown from smaller AlFe2O4 nanoparticles were 4 to 5 times higher than from bigger AlFe2O4 nanoparticles. When VA-CNTs were grown by varying the catalyst area ratio with palmitic acid, VA-CNTs with AlFe2O4 nanoparticles were longer than those grown from Fe3O4 nanoparticles and CoFe2O4 nanoparticles when the catalyst area ratio was less than 0.2. The inner diameter of VA-CNTs grown with AlFe2O4 NPs gradually decreased with decreasing catalyst area ratio and approached the original particle diameter, similar to the case with Fe3O4 NPs.