Up-converted ultraviolet luminescence of Er³⁺:BaGd₂ZnO₅ phosphors for healthy illumination

Abstract

Moderate level of exposure to the solar irradiation containing UV component is essential for health care. To incorporate the UV-emitting phosphors into the commercial YAG-based white light-emitting diode introduces the possibilities of healthy illumination to individuals’ daily lives. 1 mol.% Er³⁺-doped BaGd₂ZnO₅ (BGZ) particles were synthesized via sol–gel method and efficient up-converted luminescence peaked at 380 nm was detected under 480 nm excitation. The mixed phosphors with varied mass ratio of Er³⁺:BGZ and Ce³⁺:YAG particles were encapsulated to form LEDs. The study of the LEDs indicated that the introduction of BGZ component favored the enhancement of color-rendering index and the neutralization of the white light emitting. The WLED with the BGZ/YAG ratio of 8:2 was recommendable for its excellent overall white light luminous performances and UV intensity of 84.55 mW/cm². The UV illumination dose of the WLEDs with mixed YAG and BGZ was controllable by adjusting the ratio, the illumination distance and the illumination time. Er³⁺:BGZ phosphors are promising UV-emitting phosphors for healthy indoor illumination.

Keywords

Er³⁺:BaGd₂ZnO₅ / up-converted ultraviolet / LED / healthy illumination

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 51472263 and 51572175), the Jiangsu Planned Projects for Postdoctoral Research Funds (1501131C), and the Shanghai Planned Projects for Young Teacher Training of Universities (ZZyy15087).

RIGHTS & PERMISSIONS

2016 Higher Education Press and Springer-Verlag Berlin Heidelberg