The different structure characteristics of nanosized Co3O4 film crystallized by the annealing and plasma techniques

In this study, we deposited nano-Co3O4 film on silicon substrate using plasma-enhanced metal-organic chemical vapor deposition (PEMOCVD), and the structure difference of Co3O4 crystallized by the annealing and the Ar/O2 plasma techniques were explored by SEM, TEM, XRD, and XPS. Compared to the net morphology of Co3O4 film treated with high calcinations temperature, the cauliflowers-shaped micro-clusters were changed to nano-catkin when the sample was treated with Ar and O2 plasma for 40 min. Additionally, both samples (annealed and plasma-treated) showed the formation of both the {311} and {220} planes. The surface richness of active Co3+ sites on the exposed {220} plane indicated that the as-deposited nano-Co3O4 films have potential catalytic properties for CO and hydrocarbon oxidation.