Optical and EPR studies of Fe-doped CaAl12O19 near-infrared emitting phosphor

In this article we report our results on optical and electron paramagnetic resonance studies of Fe-doped CaAl12O19. At room temperature, optical excitation in the ultraviolet region leads to highly intensive luminescence signal at around 810 nm that is ascribed to the emission of Fe3+. Measurements at low temperature revealed slight shift of the emission maximum and appearance of additional wide luminescence bands in the blue and near-infrared parts of spectrum. The dependence of the luminescence intensity and decay time on temperature and concentration of Fe3+ in the material has been studied. Electron paramagnetic resonance studies showed presence of at least two different paramagnetic centres related to Fe3+. The nature of the observed luminescence bands is discussed.

Automated summary

In this study, we investigated the luminescence properties of Fe-doped CaAl12O19 using optical and electron paramagnetic resonance techniques. Our results revealed that Fe3+ emits intense luminescence in the infrared region under ultraviolet excitation, and additional blue and near-infrared luminescence bands appear at low temperatures. The luminescence intensity and decay time were found to depend on temperature and Fe3+ concentration.