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Photoluminescence resulting from semiconductor-metal solid solution observed in one-dimensional semiconductor nanostructures.

Yung-Jung Hsu·Shih-Yuan Lu
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Abstract

A narrow band photoluminescence (PL) emission peak resulting from CdS-Au solid solution was observed when growing one-dimensional nanostructures of CdS via the vapor-liquid-solid mechanism by using Au as the catalyst. This emission peak was located at 680 nm, a wavelength longer than the near band edge emission of CdS at 520 nm, and was shown not to be caused by the usual trap states of CdS which lead to a broad band emission. Here, the one-dimensional nanostructures of CdS were grown in a simple, low-temperature (360 degrees C) metal-organic chemical vapor deposition process with a single source precursor of CdS. Straight nanowires of diameter 50-70 nm and wormlike nanorods of diameter 100-200 nm were obtained. Both the upper and lower portions of the nanorods/nanowires possessed single crystallinity as judged from the corresponding high-resolution transmission electron microscopy images and selected area electron diffraction data. This work demonstrates the feasibility of adjusting PL emission peaks of optoelectronic semiconductors through alloying with metals.

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Cadmium CompoundsGoldLuminescenceLuminescent MeasurementsNanostructuresParticle SizePhotochemistrySemiconductorsSolutionsSulfatesSurface PropertiesLetterResearch Support, Non-U.S. Gov't

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Yung-Jung Hsu, Shih-Yuan Lu. 2004-01-06. Photoluminescence resulting from semiconductor-metal solid solution observed in one-dimensional semiconductor nanostructures.. https://doi.org/10.1021/la035138k

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