A series of highly quantum efficiency PMMA luminescent films doped with Eu-complex as promising light-conversion molecular devices

Abstract

In this paper, a series of Eu/PMMA and Eu/PMMA/SiO2 luminescent films have been designed, fabricated and characterized. Thermo-gravimetric analysis and photo-luminescence results indicated the Eu-complex precursor was successfully immobilized in PMMA matrix through the interaction between the Eu-complex and the –C=O groups of the PMMA matrix. The emission spectra of the Eu-complex and Eu/PMMA films recorded at 25 °C exhibited the characteristic bands arising from the 5D0/7FJ. The fact that the quantum efficiencies (η) of the doped film increased significantly indicated that PMMA matrix acted as an efficient co-sensitizer for Eu3+ ions luminescent center, and therefore enhanced the η of the emitter 5D0 level. Especially, with the doping nano-SiO2 into Eu/PMMA-5 % system, the T d-5 % of Eu/PMMA/SiO2 has obviously improved. Due to the carrying effect of nano-SiO2 and interaction between –C=O of PMMA chain and Eu3+ ions, the η of Eu/PMMA/SiO2 films have been greatly enhanced. To the best of our knowledge, the η of Eu/PMMA/SiO2-3 % film (78.57 %) is found to be the highest so far reported in the literature. These Eu/PMMA/SiO2 luminescent films show excellent luminescent properties and therefore have potential applications in light-conversion molecular device.