Compared to other graphitic nanostructures, in particular, the tubular geometry of carbon nanotubes, the nanopearls forming a three-dimensional foamlike material have the advantage of presenting statistically a high density of apex areas with a small radius of curvature (similar to 75 nm) when deposited at the end of a tip. This structure is suitable for a self-repairing cathode working at high currents. The field emission study was performed in a conventional field emission microscope equipped with an energy analyzer. After a conditioning process, currents up to 50 AA can be obtained under continuous emission, and the variation of the field emission current with the applied voltage strictly followed the conventional Fowler-Nordheim behavior, i.e., a linear variation of ln(I/V-2) vs (1/V). A systematic analysis of the total energy distribution spectra under different conditions has been done. For current emitted from a single nanopearl at the end of one string, the full width at half maximum (FWHM) of the single peak total energy distribution spectra is similar to 0.2 eV and it is position dependent on the string resistance. From the convolution of independent sources, associated to the foamlike structure of the carbon nanopearls, the total energy distribution spectra present a multiple peak structure with a global FWHM values from 0.5 to I eV. (c) 2006 American Vacuum Society.