Synthesis of CuO/ZnO Composite Nanostructures, Their Optical Characterization and Valence Band Offset Determination by X-Ray Photoelectron Spectroscopy
The study of the optical properties of zinc oxide (ZnO) nanorods and its composite nanostructures is an appealing issue in order to have highly efficient optoelectronic devices in the future. Zinc oxide, copper oxide (CuO) and their composite nanostructures were grown by the hydrothermal
growth technique. The structural properties of the grown ZnO, CuO and their composite NSs were investigated by scanning electron microscopy and X-ray diffraction techniques. UV-visible spectroscopy, Cathodoluminescence and photoluminescence techniques were used for the study of optical properties
of the as synthesized nanomaterials. X-ray photoelectron spectroscopy was used to measure the valence band offset of the CuO/ZnO composite nanostructures. Cathodoluminescence study of pure ZnO nanorods showed more insight for lateral luminescence compared to the top surface of the nanorods
which opened a novel investigation in the area of optical properties of ZnO nanomaterial. While the room temperature cathodoluminescence spectra of CuO/ZnO composite nanostructures have demonstrated excellent luminescence in the UV region compared to the cathodoluminescence spectra observed
at 4 K. The measured values for valence band offset and conduction band offset are found to be 2.83 eV and 0.73 eV, respectively for the prepared CuO/ZnO composite nanostructures. It was observed that CuO/ZnO composite nanostructures have type-II band alignment. The conclusion from both the
cathodoluminescence and the photoluminescence studies showed that the luminescence in the visible region is only originated from the ZnO nanomaterial and that the CuO absorbs this visible emission as it covers the ZnO. This provides evidence suggesting that the use of CuO/ZnO in the fabrication
of LEDs in the visible range is not appropriate.
Keywords: BAND OFFSET; CATHODOLUMINESCENCE; CUO/ZNO COMPOSITE NANOSTRUCTURES; PHOTOLUMINESCENCE; X-RAY PHOTOELECTRON SPECTROSCOPY
Document Type: Research Article
Publication date: 01 June 2014
- Journal of Nanoelectronics and Optoelectronics (JNO) is an international and cross-disciplinary peer reviewed journal to consolidate emerging experimental and theoretical research activities in the areas of nanoscale electronic and optoelectronic materials and devices into a single and unique reference source. JNO aims to facilitate the dissemination of interdisciplinary research results in the inter-related and converging fields of nanoelectronics and optoelectronics.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Ingenta Connect is not responsible for the content or availability of external websites
- Access Key
- Free content
- Partial Free content
- New content
- Open access content
- Partial Open access content
- Subscribed content
- Partial Subscribed content
- Free trial content