Doping homogeneity in co-doped materials investigated at different length scales. Issue 2 (16th December 2019)

• Record Type: Journal Article
• Authors: Li, Wenyu; Smet, Philippe F.; Martin, Lisa I. D. J.; Pritzel, Christian; Schmedt auf der Günne, Jörn
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 2(2019)
• Page Start: 818
• Page End: 825
• Publication Date: 2019-12-16
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp05599a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Doping homogeneity is important for the properties of co-doped phosphors, as it can affect the energy transfer between sensitizer and activator ions. Abstract : Doping homogeneity is important for the properties of co-doped phosphors, as it can affect the energy transfer between sensitizer and activator ions. In a case study we apply different methods, that is scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDX) mapping, SEM combined with cathodoluminescence (CL) and solid-state nuclear magnetic resonance (NMR), to study the doping homogeneity of the host system monazite LaPO4 doped with two different lanthanide ions on different length scales. A new criterion for doping heterogeneity in co-doped systems is developed, which is based on the NMR visibility function, which for this purpose is extended to doping with two or more paramagnetic dopants. A deviation from this function is indicative of doping heterogeneity on the length-scale of the blind-spheres of the paramagnetic dopants. A discussion of the advantages and disadvantages of the different methods is presented. The combined approach allows to study doping homogeneity from the nm to the μm scale.