A common qualitative model is proposed for explanation of phenomenon of facilitated field-induced electron emission from different types of nano-structured carbonic materials with relatively smooth surface morphology. This model represents a version of two-barrier emission mechanism where intermediary electron states are associated with conductive nano-sized objects at or near the emitter surface. ‘Hot’ electrons injected from emitter bulk have a very large lifetime in such nanoparticles. This feature allows them to travel to the vacuum boundary where they can easily leave the emitter.