Fabrication of nanocrystalline cobalt oxide via sol–gel coating

Nanocrystalline cobalt oxide thin films were fabricated by sol–gel processing method. The effect of cobalt salt amount in sol–gel mixture on film properties was investigated by means of Raman spectroscopy and atomic force microscopy. Micropatterns of these sol–gel mixtures were fabricated by spin coating followed by a lift-off method. It is generally known that sol–gel processed films are difficult to etch or remove by chemical and plasma techniques. In this novel process, cobalt oxide microstructures could be fabricated by transformation of pre-fabricated nanocrystalline cobalt oxide particles in a sol–gel process. Also, the growth of carbon nanotubes on fabricated cobalt oxide films was investigated. It was found that different size multiwall carbon nanotubes could be grown on the cobalt oxide films depending on the concentration of cobalt salt in sol–gel mixtures.