Synthesis and Field Emission Property of Highly Porous Sponge-Like Graphene

Highly porous sponge like graphene (SLG) was synthesized by chemical vapor deposition with sponge nickel as template.Pure SLG was obtained after etching away the nickel frameworks with hydrochloride acid solution.The influence of the SLG microstructures on the field emission properties was investigated with X-ray diffraction, scanning electron microscopy and Raman spectroscopy.The preliminary results show that the multilayered SLG, grown on sponge nickel, displayed good field emission properties, particularly after mechanical polishing.To be specific, the ultrahigh field enhancement factor of SLG was calculated to be over 50000;and a field emission current density of 10 μA/cm² was achieved at an on-set field of 1.8 V/μm, possibly because of the high density of protruding emission spots on the SLG stepped surface.