采用X射线吸收近边结构(XANES)谱对多晶Lu2SiO5∶Ce(LSO∶Ce)发光粉体中Ce元素的化合价状态进行了表征, 结果表明: 在空气下煅烧后得到的不同Ce掺杂浓度的LSO∶Ce粉体中, Ce3+在总掺杂Ce中的含量仅为18%～39%; 而经1 000 ℃/2 h的氢气气氛下退火后, LSO∶0.5%Ce粉体中Ce3+的相对含量由39%大幅提高到83%。真空紫外(VUV)激发发射光谱表明: 当Ce的掺杂摩尔分数为0.25%～1%时, Ce3+的摩尔分数与LSO∶Ce粉体的发光强度具有很好的关联性。 氢气退火处理可以使LSO∶Ce粉体的发光强度提高近40%。LSO∶Ce粉体在变温条件(50～250 K)下的发射强度表现出良好的稳定性, 未观察到热猝灭现象发生。

The valence state of Ce in the polycrystalline Lu2SiO5∶Ce(LSO∶Ce) luminescent powders was characterized by X-ray absorption near edge structure (XANES) spectra. The result demonstrates that Ce3+ contents relative to Ce in the LSO∶Ce powders with different Ce-doped concentration are only 18%～39%. Annealed at 1 000 ℃ for 2 h in a flowing hydrogen atmosphere, the relative Ce3+ content of LSO∶0.5%Ce powder increases significantly to 83% from 39%. The emission spectra excited by vacuum ultra violet (VUV) suggest that the luminescence intensity of LSO∶Ce with Ce mole fraction from 0.25% to 1% is correlated closely with Ce3+ content in the powders. The luminescence intensity of LSO∶0.5%Ce increases about 40% by annealing in a flowing hydrogen atmosphere. The emission intensity is very stable at different temperatures (50~250 K) without thermal quenching effect observing.