Welcome to Journal of Synthetic Crystals! Today is Jul. 14, 2025 Share:

Journal of Synthetic Crystals ›› 2025, Vol. 54 ›› Issue (5): 793-800.DOI: 10.16553/j.cnki.issn1000-985x.2024.0270

• Research Articles • Previous Articles     Next Articles

Growth and Luminescence Properties of Li2MoO4 Crystal by Bridgman Method

LIU Wenyu(), QIAN Lu, LI Fangjian, PAN Shangke(), SUN Zhigang, CHEN Hongbing, PAN Jianguo   

  1. School of Materials Science and Chemical Engineering,Ningbo University,Ningbo 315211,China
  • Received:2024-11-01 Online:2025-05-15 Published:2025-05-28

Abstract: In the research on cryogenic radiation detectors for neutrinoless double β decay, the growth and luminescence properties of Li2MoO4 crystals were studied. Commercially sourced Li2MoO4 powder was used as the starting material and was purified through the horizontal zone melting method. A 1 inch (1 inch=2.54 cm) transparent Li2MoO4 crystal was grown by Bridgman method. Phase analysis and luminescence property characterization were conducted on the crystal. X-ray powder diffraction reveals that the crystal belongs to the hexagonal system, with a space group of R3 and unit cell parameters a = 14.337 Å, b = 14.337 Å, and c = 9.589 Å. Inductively coupled plasma mass spectrometry shows that the contents of impurity elements Rb, Cs, Cu, Cr, Mn, Ni, Th and U in the crystals grown after purification were significantly reduced. Differential thermal analysis shows that its melting point is 696 ℃. The maximum optical transmittance, measured by ultraviolet-visible spectrophotometry, was found to reach 86%, indicating that the crystal has high optical quality and low impurity content. Steady-state and transient fluorescence spectra were measured, showing that the temperature-dependent fluorescence spectra and photoluminescence decay time of the Li2MoO4 crystal varied within the temperature range from 10 K to 300 K. It was observed that fluorescence intensity peaked at 10 K, while the photoluminescence decay time reduces with rising temperature, reaching 1 222.6 μs at 10 K. The activation energy Ea of the crystal is 6.15 meV. These findings suggest that the Li2MoO4 crystals grown by this method exhibit excellent luminescence properties at low temperatures, making them highly suitable for application in neutrinoless double β decay research, particularly in cryogenic radiation detectors.

Key words: neutrinoless double β decay; Li2MoO4 crystal; purification; Bridgman method; fluorescence spectrum; decay time

CLC Number: