To enhance functionality and usability of 1-D nanomaterials, the synthesis of composite nanowires such as core-shell nanowires is a good solution.  Ag-TiO₂ core-shell nanowires have attracted much attraction, because Ag nanowires have unique properties of high surface plasmon resonance as well as good electrical conductivity, while TiO₂ is an ideal material as photocatalysts.  In the absence of oxide precursors, templates, inoculants and surfactants, this study successfully prepared vertical Ag nanowires with a spontaneous ultra-thin TiO₂ shell (~0.5 nm) on TiO₂ substrate using a one step process.  STEM/EELS results demonstrate that this oxygen-deficient TiO₂ layer is formed through the oxidation of Ti which is released from the substrate and segregated to the nanowire surface simultaneously with crystal growth of the nanowires (Fig. 1).  The EELS spectra suggest that the valence of Ti ions in this spontaneous oxide layer is between Ti³⁺ and Ti⁴⁺.

Figures:

Fig. 1 Ag@TiO2-x core-shell nanowires and the corresponding EELS elemental mapping at wire edge, as well as the schematic growth mechanism

« Back to The 16th European Microscopy Congress 2016

EMC Abstracts - https://emc-proceedings.com/abstract/eels-observation-on-spontaneously-grown-agtitanium-oxide-core-shell-nanowires/