Ce3+:Lu3Al5O12–Al2O3 optical nanoceramic scintillators elaborated via a low-temperature glass crystallization route

Jie Fu (1) , Shaowei Feng (2) , Yongchang Guo (2) , Ying Zhang (2) , Cécile Genevois (3) , Emmanuel Veron (3) , Mathieu Allix (3) , Jianqiang Li (1)

1 USTB - University of Science and Technology Beijing [Beijing]
2 IPE - Institute of Process Engineering
3 CEMHTI - Conditions Extrêmes et Matériaux : Haute Température et Irradiation

Transparent Ce:lutetium aluminum garnet (Ce:Lu 3 Al 5 O 12 , Ce:LuAG) ceramics have been regarded as potential scintillator materials due to their relatively high density and atomic number (Z eff). However, the current Ce:LuAG ceramics exhibit a light yield much lower than the expected theoretical value due to the inevitable presence of Lu Al antisite defects at high sintering temperatures. This work demonstrates a low-temperature (1100 ℃) synthetic strategy for elaborating transparent LuAG-Al 2 O 3 nanoceramics through the crystallization of 72 mol% Al 2 O 3-28 mol% Lu 2 O 3 (ALu28) bulk glass. The biphasic nanostructure composed of LuAG and Al 2 O 3 nanocrystals makes up the whole ceramic materials. Most of Al 2 O 3 is distributed among LuAG grains, and the rest is present inside the LuAG grains. Fully dense biphasic LuAG-Al 2 O 3 nanoceramics are highly transparent from the visible region to mid-infrared (MIR) region, and particularly the transmittance reaches 82% at 780 nm. Moreover, Lu Al antisite defect-related centers are completely undetectable in X-ray excited luminescence (XEL) spectra of Ce:LuAG-Al 2 O 3 nanoceramics with 0.3-1.0 at% Ce. The light yield of 0.3 at% Ce:LuAG-Al 2 O 3 nanoceramics is estimated to be 20,000 ph/MeV with short 1 μs shaping time, which is far superior to that of commercial Bi 4 Ge 3 O 12 (BGO) single crystals. These results show that a low-temperature glass crystallization route provides an alternative approach for eliminating the antisite defects in LuAG-based ceramics, and is promising to produce garnet-based ceramic materials with excellent properties, thereby meeting the demands of advanced scintillation applications.

Mots clés: glass crystallization garnet antisite defects Lu; glass crystallization; garnet antisite defects; Lu

Domaines: Matériaux

Jie Fu, Shaowei Feng, Yongchang Guo, Ying Zhang, Cécile Genevois, et al.. Ce3+:Lu3Al5O12–Al2O3 optical nanoceramic scintillators elaborated via a low-temperature glass crystallization route. Journal of Advanced Ceramics, 2023, 12 (2), pp.268-278. ⟨10.26599/JAC.2023.9220681⟩. ⟨hal-04305583⟩