Role of Ln type in the physical mechanisms of defect mediated luminescence of Li, Ln-SnO2 nanoparticles
METADATA ONLY
Loading...
Author / Producer
Date
2021
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
METADATA ONLY
Data
Rights / License
Abstract
Doping SnO2 with trivalent lanthanide (Ln) metals aiming at optical applications faces several challenges. The elastic and electrostatic misfit between bulkier Ln activators and Sn host cation induces strain in the lattice as well as defects as a result of charge-compensation. These effects can be partially healed by thermal annealing. However, dopant segregation which occurs above a certain temperature drives quenching of Ln emission. In this work, we explore Li co-doping as a vehicle to improve the luminescence of lanthanide (Eu, Sm, Er, Dy and, Tb) doped SnO2 nanoparticles. In case of substitutional Ln dopants (Eu, Sm and Er), Li enhances significantly the Ln luminescence up to 40-46 times. The luminescence enhancement induced by Li co-doping is explained by an interplay of removal of nearby oxygen vacancies (Eu, Sm), improved Ln doping homogeneity (Er) and, improved crystallinity (Eu, Sm, Er). The improved crystallinity caused by Li co-doping accounts for less than 30% of the total enhancement. In the case of surface Ln dopants (Dy and Tb), Li co-doping does not alter the Ln emission, either in shape or intensity. Only a few Dy dopants succeed to substitute for Sn in the rutile lattice as shown by single-photon counting investigations. Collectively, our results show that the extent of luminescence enhancement induced by Li co-doping depend strongly on the Ln type. In SnO2, the common mechanisms that explain the Li induced enhancement of Ln luminescence in various hosts, either contribute partially (improved crystallization) or do not contribute at all (local structure distortion). This journal is © The Royal Society of Chemistry.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
9 (1)
Pages / Article No.
148 - 157
Publisher
Royal Society of Chemistry
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Organisational unit
02891 - ScopeM / ScopeM