Effect of thickness and substrate type on the structure and low vacuum photoemission of carbyne-containing films.

Monoatomic carbon chains and carbyne-rich composites are promising materials for many applications from protective coatings to nanoelectronic devices. Therefore, a thorough understanding of both the atomic and electronic structure of chained carbon is important. In this study, a combination of Raman scattering and electron photoemission techniques is used to study the bonding types, electron work functions and band gaps for carbyne-containing films on copper and silicon substrates. Raman mapping shows the nonuniform distribution of sp1 hybridization across the carbon-coated area on polycrystalline copper substrate due to adhesion differences. UV-excited electron emission dependence on thickness and ambient pressure confirms the difference between the silicon- and copper-based samples. Comparison with DFT calculations performed on surface slab models allows to draw conclusions about the chained composite structure. Image 106 [ABSTRACT FROM AUTHOR]