Size dependent carrier recombination in ZnO nanocrystals
2010 (English)In: APPLIED PHYSICS LETTERS, ISSN 0003-6951, Vol. 97, no 13, 131909- p.Article in journal (Refereed) Published
Experimental and theoretical studies of fluorescence decay were performed for colloidal ZnO nanocrystals. The fluorescence lifetime reduces from 22 ps to similar to 6 ps with decreasing nanocrystal radius. We postulate that non-radiative surface states dominate the carrier dynamics in small ZnO nanocrystals and perform Monte Carlo simulations incorporating carrier diffusion and carrier recombination to model the experimental fluorescence decay dynamics. The percentage of excitons undergoing nonradiative decay due to surface trapping is as high as 84% for nanocrystals with 8 nm radius, which explains the ultrafast decay dynamics observed in small ZnO nanostructures even at low temperatures.
Place, publisher, year, edition, pages
American Institute of Physics , 2010. Vol. 97, no 13, 131909- p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-61208DOI: 10.1063/1.3494535ISI: 000282443800028OAI: oai:DiVA.org:liu-61208DiVA: diva2:360868
Galia Pozina, Li-Li Yang, Qingxiang Zhao, Lars Hultman and P G Lagoudakis, Size dependent carrier recombination in ZnO nanocrystals, 2010, APPLIED PHYSICS LETTERS, (97), 13, 131909.
Copyright: American Institute of Physics