CW EPR Investigation of Red-Emitting CaS:Eu Phosphors: Rationalization of Local Electronic Structure - data

A series of commercial and prepared CaS:Eu2+ rare earth activated phosphors are investigated following different post-synthetic treatments. A number of species directly related to the function of the material are characterized using electron paramagnetic resonance (EPR) spectroscopy. Isolated Eu2+ sites are identified and associated with the substitutional doping for Ca2+ in the lattice which are responsible for the 645 nm emission of interest. Another inactive Eu2+ site based within a “EuO” type phase aggregated on the surface of the material is also identified, as well as competitive F+ center defects that are known to reduce emission from the Eu2+ sites. Intrinsic Mn2+ impurities are identified and used as local order probes to determine changes in ordering and symmetry upon cryo-milling and heating treatments of the samples. X-ray photoelectron (XPS) and photoluminescence (PL) spectroscopies are also conducted to complement the local structure observations. The reported data is useful in understanding how the nature of the lattice affects ground state electronic structure of functional defective sites, for the development of efficient and selective materials.

The datasets are in a single excel spreadsheet (.xlsx) in text format, containing all of the presented data Figures 1-6; Figures S1-13 (Supporting information); with a description of the contents included in the first worksheet. The dataset contains, in general: multi-frequency electron paramagnetic resonance (EPR) spectroscopy data of all reported samples, experimental and simulated using the EasySpin toolbox in MATLAB (see main paper for reference), corresponding to Figures 1-4, S1-S7; X-ray photoelectron spectroscopy (XPS) data of CaSEu_1, CaSEu_2, CaSEu_3, CaSEu_SSR including experimental survey, high resolution region measurements, and fitted simulations using the CasaXPS program (see main paper for reference), corresponding to Figures 5, S11 12 13; Experimental luminescence spectroscopy data of CaSEu_1, CaSEu_2, CaSEu_Na, CaSEu_Na_C3, CaSEu_SSR corresponding to Figure 6. 

Reserach results based upon these data are published at http://doi.org/10.1002/adom.202001241