Magnetic resonance study of acceptors in ZnO nanocrystals
EMSL Project ID
47648
Abstract
In our previous work, we used the X-band EPS spectrometer at EMSL to detect signatures of acceptor defects in ZnO nanocrystals. These acceptors give rise to a series of sharp IR peaks due to electronic transitions. The nanocrystals in that study were synthesized at WSU and had diameters of ~20 nm. Our subsequent work, using the high-field EPR system, revealed fine structure in the EPR resonance near g ~ 2. There is evidence for two centers, one axial and one isotropic. Our final experiment uses commercial nanopowder (Aldrich, <100 nm diameter). The commercial sample shows a strong IR acceptor signature. In the proposed work, EPR spectra will be obtained from the commercial powder. The high-field system at EMSL is perfectly suited to this study. We expect that the sample will show a strong EPR signature, allowing us to tie together the IR and electron-spin properties of the acceptor defect. This is important because the microscopic structure of this defect is currently unknown. The results from this work will be published in an article and will go into a Ph.D. dissertation that will be defended on July 13, 2012.
Project Details
Project type
Limited Scope
Start Date
2012-06-26
End Date
2012-08-26
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Mccluskey MD, C Corolewski, J Lv, MC Tarun, ST Teklemichael, ED Walter, MG Norton, KW Harrison, and SY Ha. 2015. "Acceptors in ZnO." Journal of Applied Physics 117:112802. doi:10.1063/1.4913827