Hydrothermal synthesis, structure and scintillation characterization of nanocrystalline Eu-doped Gd2O3 materials and its X-ray imaging applications

Nanocrystalline Gd₂O₃:Eu scintillators were successfully synthesized using a hydrothermal method and subsequent calcination treatment in the electrical furnace as an X-ray to visible light conversion material for an indirect X-ray image sensor. In this work, various Gd₂O₃:Eu scintillators were prepared in accordance with different synthesis conditions such as doped-Eu concentration, different calcination temperatures of 600-1400 °C and calcination time of 1-10 h. The transition of morphology from nanorods to particles was observed as the calcination temperature of Gd₂O₃:Eu scintillator increased. And the phase transformation of the sample from cubic to monoclinic structure was discovered at 1300 °C calcination temperature. In addition, scintillation properties such as luminescent spectra and light intensity under 266 nm UV illumination were measured as a function of calcination condition of as-synthesized Gd₂O₃:Eu powder. The nanocrystalline Gd₂O₃:Eu scintillator with a strong red light emission at near 611 nm wavelength under photo- and X-ray excitation will be employed for its potential X-ray image sensor applications in the future.