【摘 要】
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Yb3+-doped phosphors have characteristic near-infrared(NIR)emissions,but their applications in phosphor-converted light-emitting-diodes(pc-LEDs)and Si solar cells are limited due to their mis-matching excitation spectra.Here,we selected nitride La3Si6N11(
【机 构】
：
The Beijing Municipal Key Laboratory of New Energy Materials and Technologies,School of Materials Sc
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Yb3+-doped phosphors have characteristic near-infrared(NIR)emissions,but their applications in phosphor-converted light-emitting-diodes(pc-LEDs)and Si solar cells are limited due to their mis-matching excitation spectra.Here,we selected nitride La3Si6N11(LSN)as host material to achieve Yb3+NIR emission upon low-energy charge transfer(CT)excitation.The obtained phosphor LSN∶Yb3+has a broad CT excitation band ranging from 250 to 500 nm and narrowband NIR emissions ranging from 950 to 1100 nm centered at 983 nm.On the basis of spectral data,the vacuum referred binding energies(VRBE)schemes are constructed to locate energy levels of all lanthanide ions in LSN.We also fabricated NIR pc-LED device using 395 nm LED chip to demonstrate the potential applications of LSN∶Yb3+phosphors.
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