Comment on 'Metallic nanowire-graphene hybrid nanostructures for highly flexible field emission devices'

Comments are made on theoretical aspects of a recent paper on cold field electron emission (CFE) from a large area field emitter (LAFE), in Arif et al (2011 Nanotechnology 22 355709). (1) Anomalies in the extraction of characterization parameters from the published graphical data are corrected. (2) Quantitative tests show that the data are not compatible with the hypothesis that the measured current is controlled by an orthodox CFE process. Hence, it may not be possible to interpret the extracted slope characterization parameter as a simple electrostatic field enhancement factor. (3) The Fowler-Nordheim-type equation used is defective, because it is missing an important pre-exponential correction factor, and would over-predict LAFE-average current density by a very large factor.