Upconversion Luminescence of HfO2 Phosphors Embedded into Polyester FILMS
This powders and films were optical, structural and luminescent characterized using x-ray diffraction, electron microscopy, IR spectroscopy and UV-Vis. A study of the infrared to green and infrared to red UC processes was performed including the analysis of the spectral and the temporal behavior. The mechanisms contributing to the UC luminescence were identified as excited state absorption and energy transfer among rare earth ions. (x, y) coordinates of CIE diagrams are reported also.
Finally, it is important to sight, that this kind of phosphors attached at polymeric films could be eventually incorporated to solar cells in order to increase its nominal efficiency.
1. François Auzel, Upconversion and Anti-Stokes Processes with f and d Ions in Solids, Chemical Reviews 2004 104 (1), 139-174
2. S. Carmona-Téllez, G. Alarcón-Flores, A. Meza-Rocha, E. Zaleta-Alejandre, M. Aguilar-Futis, H. Murrieta S and C. Falcony, Polyethylene terephthalate thin films; a luminescence study, Optical Materials, 42, 2015, 99–105.