研究了Li+和Er3+共掺Y2O3纳米晶体粉末的上转换发光特性，并重点分析了Li+的掺杂浓度对粉末晶形结构和发光强度的影响。结果表明，采用燃烧法制备出来的样品在Li+掺杂浓度较高的情况下仍能保持良好的晶型，随着Li+共掺浓度的增大，Er3+Y2O3纳米晶体在绿光和红光波段的上转换发光强度有了显著的提高。造成发光增强的原因是Li+的引入改变了Er3+Y2O3的晶格对称性，从而提高了Er3+中4f组态内层电子的跃迁几率。

The upconversion luminescent properties are investigated in Li+ and Er3+ codoped Y2O3 nanocrystals, especially the effect of the Li+ molar fraction on the crystalline structure and the luminescent intensity. Results indicate that the samples prepared by combustion method have good crystallinity even with high Li+ codoping concentration. The luminescent test results show that with the increase of the Li+ codoping concentration, the upconversion luminescent intensity of the nanocrystals in green and red range will enhance remarkably. The lattice symmetry of the nanocrystals is modified by codoping Li+, which increases the intra-4f transition probability in Er3+.