▎ 摘　　要

The evolution of morphology, structure and plasmonic properties in graphene nanowalls (GNWs) with change in Ar:CH4 ratio in plasma enhanced chemical vapour deposition is studied. Open channel morphology at 7:1 and secondary growth with high corrugation at 1:1 and 1:7 Ar:CH4 ratios are corroborated with process parameters. Raman spectra are explained based on the defects in graphene structure. The absence of symmetric stretch vibrations of methyl and methylene groups in FTIR studies are correlated with electron diffraction patterns. TEM and electron diffraction studies showed that GNWs have higher d-spacing (0.36 to 0.42 nm) than of highly oriented pyrolytic graphite (HOPG) (0.34 nm). Among the samples, the one synthesized at 1:1 ratio is found to have lowest d-spacing, fewer layers and better long range order. The pi-pi* plasmonic peak positions are corroborated with abundance of hydrocarbon species attached to the surfaces and edges of GNWs. GNWs register identical C K-edge and sp(2) bonding fraction. However, the C K-edge of GNWs was red shifted in comparison to HOPG. The relative abundance of hydrocarbon species influences the evolution of morphology, structure and plasmonic properties.