Academic Journal
Low temperature near band edge recombination dynamics in ZnO nanorods
| Title: | Low temperature near band edge recombination dynamics in ZnO nanorods |
|---|---|
| Authors: | Urgessa, Z. N., Botha, J. R., Eriksson, Martin O., Mbulanga, C. M., Dobson, S. R., Tankio Djiokap, S. R., Karlsson, K. Fredrik, Khranovskyy, Volodymyr, Yakimova, Rositsa, Holtz, Per-Olof |
| Publisher Information: | Linköpings universitet, Halvledarmaterial Linköpings universitet, Tekniska högskolan Nelson Mandela Metropolitan University, South Africa American Institute of Physics (AIP) |
| Publication Year: | 2014 |
| Collection: | Linköping University Electronic Press (LiU E-Press) |
| Subject Terms: | Chemical Sciences, Kemi |
| Description: | The recombination dynamics of neutral donor bound excitons ((DX)-X-o: I-4, I-6/6a) and near band edge defect-related emission in solution grown ZnO nanorods are investigated using steady state and time-resolved photoluminescence (PL) measurements. The effects of annealing are also studied. Low temperature steady state PL shows a systematic removal of the I-4 line after annealing at 450 degrees C and the subsequent domination of I-6a in these PL spectra. Additionally, the time decay of the I-4, I-6/6a, free exciton (FX), and basal plane stacking fault-related (BSF) PL transitions are studied as a function of annealing temperature. For the various annealing temperatures studied, the PL decay is described by a bi-exponential profile with a fast component (contribution from the surface) and slow component (related to bulk recombination). The fast component dominates in the case of as-grown and low temperature annealed samples (anneal temperatures up to 300 degrees C), suggesting the presence of surface adsorbed impurities. For samples annealed above 400 degrees C, the effects of the surface are reduced. The sample annealed at 850 degrees C produced an overall enhancement of the crystal quality. The underlying mechanisms for the observed PL characteristics are discussed based on near surface band bending caused by surface impurities. ; Funding Agencies|South Africa Research Chairs Initiative of the Department of Science and Technology; National Research Foundation (NRF), South Africa; Nelson Mandela Metropolitan University (NMMU); Swedish-South Africa research collaboration |
| Document Type: | article in journal/newspaper |
| File Description: | application/pdf |
| Language: | English |
| ISBN: | 978-0-00-342840-7 0-00-342840-0 |
| Relation: | Journal of Applied Physics, 0021-8979, 2014, 116:12, s. 123506-; http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112055; ISI:000342840000018 |
| DOI: | 10.1063/1.4896488 |
| Availability: | https://doi.org/10.1063/1.4896488 http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112055 |
| Rights: | info:eu-repo/semantics/openAccess |
| Accession Number: | edsbas.146F256C |
| Database: | BASE |
| Description not available. |