BaF2 Nanocrystals Research Articles

Eu2+‐Doped Glass Ceramics Containing BaF2 Nanocrystals as a Potential Blue Phosphor for UV‐LED

The Eu2+‐doped glass ceramics containing BaF2 nanocrystals were prepared and their luminescence properties were investigated. The excitation spectra of Eu2+‐doped glass ceramics showed an excellent overlap with the main emission region of an ultraviolet light‐emitting diode (UV‐LED) centered at 380 nm. The 450 nm emission of Eu2+ in glass ceramics under the 385 nm excitation was much stronger than that in glass. The Eu2+‐doped glass ceramics containing BaF2 nanocrystals may be used as a potential blue‐emitting phosphor for UV‐LED.

Cooperative Quantum Cutting of Nano-Crystalline BaF2:Tb3+, Yb3+ in Oxyfluoride Glass Ceramics

We report on cooperative quantum cutting in Tb3+-Yb3+ codoped glass ceramics. Precipitation of BaF2 nano-crystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb3+ ions under 485 nm excitation indicates cooperative energy transfer from Tb3+ to Yb3+. The quantum efficiency of this process reaches 145%. The realization of quantum cutting in glass ceramics may have promising applications in solar cells.

Spectroscopic properties of Er3+–Yb3+ co-doped glass ceramics containing BaF2 nanocrystals

A Er3+ and Yb3+ co-doped transparent oxyfluoride glass ceramic containing BaF2 nanocrystals has been prepared. The formation of BaF2 nanocrystals in the glass ceramic was confirmed by X-ray diffraction. Intense upconversion luminescence in the Er3+ and Yb3+ co-doped glass ceramic could be observed. Stark splitting of the Er3+ upconversion luminescence peaks in the glass ceramic indicated that Er3+ and Yb3+ had been incorporated into the BaF2 nanocrystals. Near infrared luminescence decay curves showed that the Er3+ and Yb3+ co-doped glass ceramic had higher luminescence efficiency than the precursor glass.

Luminescence behavior of Er3+ in glass ceramics containing BaF2 nanocrystals

The upconversion luminescence and near infrared luminescence of the Er3+ ions in transparent oxyfluoride glass ceramics containing BaF2 nanocrystals have been investigated. The formation of BaF2 nanocrystals in the glass ceramics was confirmed by X-ray diffraction and transmission electron microscopy. Stark split peaks of the near infrared emission of the Er3+ doped glass ceramics can be observed. The upconversion luminescence intensity of Er3+ in the glass ceramics increased significantly with increasing annealing time. The transition mechanisms of the upconversion luminescence have been ascribed to a two-photon process.