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Silicon nanowires (SiNWs) have been grown on crystalline silicon (Si), indium tin oxide (ITO) and stainless steel (SS) substrates using a gold catalyst coating with a thickness of 200 nm via pulsed plasma-enhanced chemical vapor deposition (PPECVD). Their morphological, mineralogical and surface characteristics have been investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman analysis. SiNWs growth is accompanied by oxidation, thus yielding partially (SiO) and fully oxidized (SiO) Si sheaths. The mean diameters of these SiNWs range from 140 to 185 nm. Si with (111) and (220) planes exists in SiNWs grown on all three substrates while Si with a (311) plane is detected only for Si and ITO substrates. Computational simulation using density functional theory (DFT) has also been conducted to supplement the experimental Raman analyses for crystalline Si and SiO. XPS results reveal that ca. 30 % of the SiNWs have been oxidized for all substrates. The results presented in this paper can be used to aid selection of appropriate substrates for SiNW growth, depending on specific applications. [ABSTRACT FROM AUTHOR]

Abstract: New cobalt-based metal oxide thin films (MxCoyOz with M=Mn, Cu, Ni) have been deposited on commercial aluminum and glass substrates using sol–gel dip-coating method. The as-deposited films were characterized by a wide range of complementary techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), spectrophotometry and nanoindentation techniques. A light absorption study for coatings on glass substrates within a wavelength range of 300–1100nm was also conducted. Topographical and morphological investigations showed the presence of nano-sized, grain-like particles in the copper–cobalt oxide coatings, which consequently had the roughest surface among the three coatings. All coatings on glass substrate exhibited higher absorption of ultraviolet (UV) light compared to visible light, while coatings on aluminum substrate generally had low reflectance (<50%) of UV light, moderate reflectance (<80%) of visible light and high reflectance (up to 100%) of infrared light. Implications of optical properties as a function of film thickness controlled by dip-heating cycles were discussed. The elastic modulus (E) and hardness (H) of thin film samples compared with stand‐alone commercial aluminum substrate were also measured. [Copyright &y& Elsevier]