Kennedy, OW; White, ER; Howkins, A; Williams, CK; Boyd, IW; Warburton, PA; Shaffer, MSP; (2019) Mapping the Origins of Luminescence in ZnO Nanowires by STEM-CL. Journal Of Physical Chemistry Letters , 10 (3) pp. 386-392. 10.1021/acs.jpclett.8b03286.

Preview

Text Kennedy_acs.jpclett.8b03286.pdf - Published Version Download (3MB) | Preview

Abstract

In semiconductor nanowires, understanding both the sources of luminescence (excitonic recombination, defects, etc.) and the distribution of luminescent centers (be they uniformly distributed, or concentrated at structural defects or at the surface) is important for synthesis and applications. We develop scanning transmission electron microscopy−cathodoluminescence (STEM-CL) measurements, allowing the structure and cathodoluminescence (CL) of single ZnO nanowires to be mapped at high resolution. Using a CL pixel resolution of 10 nm, variations of the CL spectra within such nanowires in the direction perpendicular to the nanowire growth axis are identified for the first time. By comparing the local CL spectra with the bulk photoluminescence spectra, the CL spectral features are assigned to internal and surface defect structures. Hyperspectral CL maps are deconvolved to enable characteristic spectral features to be spatially correlated with structural features within single nanowires. We have used these maps to show that the spatial distribution of these defects correlates well with regions that show an increased rate of nonradiative transitions.

Download activity - last month

Export as XMLJSONCSV

Download activity - last 12 months

Export as CSVJSONXML

Downloads by country - last 12 months

Export as CSVXMLJSON

Archive Staff Only

View Item