Cathodoluminescence of defects in sintered tin oxide

Abstract

Cathodoluminescence ͑CL͒ in the scanning electron microscope ͑SEM͒ has been used to investigate the luminescence mechanisms in tin oxide. Sintered material prepared from high purity powder has been found to show a strong dependence of the CL emission on the thermal treatments applied during sample preparation. SEM images show the presence of nano and microcrystalline grains. The correlation of the grain size and morphology with the optical emission is analyzed by CL microscopy and spectroscopy. The main emission bands appear centered at about 2.58, 2.25, and 1.94 eV depending on the sintering treatment. CL images reveal that the 2.25 and the 2.58 eV bands are associated at specific crystal faces. The evolution of the luminescence bands with mechanical milling shows a complex evolution of the 1.94 and 2.58 eV emissions which is explained by formation and recovery of defects during milling.

Growth and luminescence properties of micro- and nanotubes in sintered tin oxide

“…Further details on the dependence of the CL spectra on annealing temperature and milling treatment were also reported in Ref. 12. In this work we report the new tubular structures growing in the samples during annealing under a moderate flow of argon.…”

“…In samples prepared from a ball milled powder, the particle size varied from about 130 nm to about 60-70 m in the same temperature range of sintering. We have previously reported 12 that the CL spectra and CL intensity of the samples depend on the annealing temperature. In the different spectra, luminescence bands centered at about 1.94, 2.25, and 2.58 eV were observed.…”

Thermal growth and structural and optical characterization of indium tin oxide nanopyramids, nanoislands, and tubes

“…8,14 Since the tubes grown in this work contain only about 1 at. % of In, we suggest that the CL emission from the tubes ͓Fig.…”

Defect study of SnO2 nanostructures by cathodoluminescence analysis: Application to nanowires

“…Since the mid-1970s, however, few works have been published presenting the CL spectra of SnO 2 with different morphologies [4,5,6,7]. In all known cases, several bands between 1.9 and 2.6eV have been reported but there still remains some uncertainty on their origin [6]. However, there are no systematic and detailed works considering nanowires and their comparison with nanoparticles of different sizes.…”

“…This article will deal with the analysis of point defects using cathodoluminescence (CL) spectra of nanostructured SnO 2 , as this technique reveals complementary information about radiative transitions related to these point defects that is not determined by other characterization techniques This experimental procedure is not new. Since the mid-1970s, however, few works have been published presenting the CL spectra of SnO 2 with different morphologies [4,5,6,7]. In all known cases, several bands between 1.9 and 2.6eV have been reported but there still remains some uncertainty on their origin [6].…”