In-situ X-ray photoemission spectroscopy (XPS) has been used to investigate the initial stages of TiO2 growth on a Si(001) substrate by atomic layer deposition (ALD). The core level spectra of Si 2p, C 1s, O 1s, and Ti 2p were measured at every half reaction in the titanium tetra-isopropoxide (TTIP)–H2O ALD process. The ligand exchange reactions were verified using the periodic oscillation of the C 1s concentration, as well as changes in the hydroxyl concentration. XPS analysis revealed that Ti2O3 and Si oxide were formed at the initial stages of TiO2 growth. A stoichiometric TiO2 layer was dominantly formed after two cycles and was chemically saturated after four cycles.

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The field emission ͑FE͒ properties of ZnO and NiO-coated ZnO ͑NiO / ZnO͒ nanorods are investigated under vacuum of 7 ϫ 10 −7 Torr and oxygen rich vacuum of 1 ϫ 10 −5 Torr. The ZnO nanorods were synthesized on a Si͑100͒ substrate by metal-organic chemical vapor deposition, and the NiO film with the thickness of ϳ15 nm was coated by using atomic layer deposition. The turn-on voltages of the NiO / ZnO nanorod and the ZnO nanorod were ϳ5.2 and ϳ3.0 V / m at 1 A / cm 2 , respectively. The electron FE stability of the NiO / ZnO nanorods to the ZnO nanorod was significantly improved in oxygen rich vacuum even.

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Highly flexible, transparent, and conducting sheet was fabricated by decoration of uniformly sized gold nanoparticles (Au NPs) with high-density on large-area graphene by MeV electron beam irradiation (MEBI) at room temperature under ambient conditions. The Au NPs with an average size of 13.6 ± 3.5 nm were clearly decorated on the graphene after MEBI with an irradiation energy of 1.0 MeV. The sheet resistances of the Au NPs/graphene significantly decreased. For the Au NPs/trilayer graphene, the sheet resistance reached to ∼45 Ω/sq, and the optical transmittance was ∼90.2% which is comparable to that of conventional indium tin oxide film.