Physical Mechanism of Blue-Shift of UV Luminescence of a Single Pencil-Like ZnO Nanowire

Abstract

Cathodoluminescence spectroscopy is used to address the ultraviolet (UV) luminescence of a single pencil-like ZnO nanowire whose diameter gradually reduces from bottom to top in the range of 700-50 nm. It is found that the UV emission energy evidently shifts to the high energy with the ZnO nanowire's diameter decreasing and the blue-shift of 90 meV is observed when the nanowire diameter reduces to 50 from 700 nm. The physical mechanism of the UV blue-shift of the ZnO nanowire is attributed to the Burstein-Moss effect under the high carrier concentration.

Fabrication of Hierarchically Porous Reduced Graphene Oxide/SnIn4S8 Composites by a Low-Temperature Co-Precipitation Strategy and Their Excellent Visible-Light Photocatalytic Mineralization Performance

“…The Temporal Change of UV-Visible Spectra during the Photocatalytic Degradation Figure 9 shows the UV-Visible spectral changes during the photocatalytic degradation of RhB under visible-light irradiation. As the reaction proceeds, the maximum absorption wavelength of RhB at 554 nm disappear quickly, and there are obvious hypsochromic shifts in the maximum absorption peak position, which shifts from 554 to 510 nm [42]. Moreover, the absorption intensity decreases.…”

Characterization, Cathodoluminescence, and Field‐Emission Properties of Morphology‐Tunable CdS Micro/Nanostructures

“…The centers of the NBE emissions shifted gradually from 531 to 525 nm with decreasing diameter. This energy shift for nanotips with diameters far beyond the quantum confinement regime is referred to as the ''anomalous blueshift''; it is attributed to the surface effect (increased surface-to-volume ratios), [47,48] or the Burstein-Moss band-filling effect under excitation by a high-energy electron-beam, [49] or different impurity distributions. The intensity ratio between the DL and NBE emissions (I DL /I NBE ) with different diameters was found to be size-related in ZnO nanowires.…”

Fabrication of Fe nanowires on yittrium-stabilized zirconia single crystal substrates by thermal CVD methods

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