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Silicon oxide nanowires SiOx were synthesized by the gas‐jet electron beam plasma chemical vapor deposition method. The synthesis of nanostructures was carried out on silicon substrates with thin tin film as a catalyst. The evolution in the morphology of the obtained structures was investigated while changing the substrate temperature in the range 200–415 °C. Dense array of aligned nanowire bundles (microropes) is formed at a temperatures of 335 and 415 °C. With decrease in the temperature to 270 and 245 °C arrays of microropes transform into cocoon‐like structures of nanowires. At a temperature 200 °С, array formed almost entirely consisting of cocoon‐like structures. The results of X‐ray energy dispersive spectroscopy (EDS) of the nanowires show that the ratio of oxygen to silicon is on average Si:O = 1:2.4. At the same time, Fourier Transform Infrared spectroscopy (FTIR) analysis of the obtained nanostructures showed that the synthesized nanowires consist of SiOx with x around 2. Moreover, the composition of the structures remains practically unchanged with the variation of the substrate temperature. The IR spectra show bands due to both Si–OH bonds and water molecules. Measurements of contact angles for water showed that the nanowire film surface synthesized in this work is hydrophilic in nature. When structuring involves the oriented growth microropes, the contact angle is about 20–35°. Decreasing of the substrate temperature and formation of cocoon‐like structures leads to a decrease in the contact angle to 4–12°. The photoluminescence (PL) spectra of nanostructures synthesized at the different substrate temperatures consist of a broad band with a maximum around 2.5 eV when using laser at 325 nm as the exciting source. We assume that the composition of the nanowires is close to SiO2, and the excess of oxygen in structures composition is due to the influence of adsorbed water molecules and hydroxyl groups with the formation of Si–OH bonds. Apparently, these bonds define the photoluminescence spectrum.

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Silica nanowires were synthesized from mixture monosilane with hydrogen by gas‐jet electron beam plasma chemical vapor deposition method for the first time. The synthesis was carried out on silicon substrate with up to micrometer‐sized particles of Sn catalyst. SEM observations show that this method provides different morphology of the nanowires and catalyst. Oriented arrays of silica nanowires bunches (microropes) were synthesized in the area corresponding to the mixture jet axis. Cocoons‐like, bamboo‐like, and jellyfish‐like morphology was observed in the area corresponding to periphery of the jet. Probably there was realised vapor‐liquid‐solid (VLS) growth mechanism, where multiple nanowires grow simultaneously from the surface of one catalyst drop. The growth rate of the microropes is about 25 nm/s at synthesis temperature 330 °C. Possible growth model has been suggested in order to explain the results. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)