Carbon–ZnO nanocomposite thin films for enhanced electron field emission characteristics prepared by continuous wave CO2 laser ablation

• C–ZnO nanocomposite is fabricated by CO2 laser assisted evaporation technique.
• Technique presents an easy, single step process for growth of nC–ZnO nanocomposite.
• Growth process is explained on the basis of laser target material interaction.
• Enhanced electron emission is observed for nC–ZnO nanocomposites.
• nC–ZnO shows low turn on field and high current density from pristine carbon films.

A composite structure made by blending of nanostructured carbon (nC) and ZnO, was efficiently grown by a continuous wave CO2 laser assisted laser ablation method. The synthesis includes the growth of this composite material in a single experiment. A detail mechanism of interaction between the target material and impinging laser beam is explained. By adjusting the laser power nC–ZnO composites were efficiently fabricated. Scanning and transmission electron microscopy studies showed that the ZnO formed bead-shaped nanoparticles on carbon matrix. The experimental results showed that the composite structure (nC–ZnO) exhibit improved turn on field ∼2.2 V/μm compared to carbon matrix without ZnO coating (∼3.7 V/μm). It was observed that the presence of ZnO on the carbon matrix reduces the work function of composite structure due to charge transfer process at interface. The strong van der Walls forces act at the interface result the quite fast charge transfer at interface. Thus, the electron field emission studies present the efficient electronic properties of nC–ZnO composites and have the potential for future application in display devices.