Deposition process of laminar pyrocarbon from propane

The deposition mechanisms of smooth laminar (SL) and rough laminar (RL) pyr ocarbons from propane are found to be very different, as evidenced by (i) g as phase analysis, (ii) nucleation experiments and (iii) analysis of the de posit composition and nanostructure. SL pyrocarbon results mainly from alip hatic species; its nucleation needs surface reactive sites where chemisorpt ion and hydrogen abstraction occur; its growth leads to extended but highly distorted graphene layers which can enclose internal nanoporosity. RL pyro carbon results mainly from polycyclic aromatic hydrocarbons (PAH); its nucl eation, which does not depend on the substrate, occurs widely by physisorpt ion of PAH; the corresponding graphene layers are not very extended but par allel to each other and parallel to the anisotropy plane.