Carbon dioxide-assisted fabrication of self-organized tubular carbon micropatterns on silicon substrates

Hierarchical three-dimensional (3D) tubular micropatterns made of carbon nanotubes (CNTs) are fabricated on silicon substrates by catalytic decomposition of a ferrocene–cyclohexane mixture at 850 °C in the presence of CO2. It is found that the catalyst concentration, temperature and the presence of CO2 are key factors that govern the assembly and growth of CNTs. The self-assembled patterns of catalysts in the initial stage are responsible for the formation of CNT patterns in which a multi-level self-assembly is involved. The potential use of the tubular CNT micropatterns as electrode in the electroanalysis of biomolecules (dopamine) has been demonstrated.