Multi-functionality of luminescent glasses for energy applications. (13th August 2015)

• Record Type: Journal Article
• Authors: Steudel, F; Loos, S; Ahrens, B; Schweizer, S
• Is Part Of: Physica scripta. Volume 90:Number 9(2015:Sep.)
• Publication Date: 2015-08-13
• Subjects: photon conversion -- borate glass -- rare-earth ion doping; Physics -- Periodicals; 530.05
• DOI: 10.1088/0031-8949/90/9/094004
• Languages: English
• ISSNs: 0031-8949

Abstract

Abstract: Rare-earth-(RE) doped barium borate glasses are investigated for their potential use as photon downshifting cover glasses for CdTe solar cells and as converters for white light-emitting diodes (LEDs). The glasses are doped with trivalent RE ions such as Eu 3+ and Tb 3+, resulting in an intense luminescence in the red (Eu 3+ ) and green (Tb 3+ ) spectral range upon excitation in the ultraviolet and blue ranges. Doping the glasses with two different RE ions enables broader absorption, which is necessary for both photovoltaic applications and for the appropriate color mixing needed for use in white LEDs. Though the single-doped cover glasses already reveal a slight increase in the short-circuit current density of CdTe solar cells, the double-doped glasses allow for even higher efficiency gains due to the significantly broader spectral range for absorption. For an Eu 3+ /Tb 3+ double-doped glass with an RE doping level of 1 at.% each, an efficiency increase of 1.32% can be achieved. Furthermore, the Eu 3+ /Tb 3+ double-doped glasses enable appropriate color mixing in the green-to-red spectral range by varying the RE doping level accordingly.