La、Ce掺杂ZnO纳米晶的发光特性

Photoluminescent Properties of La and Ce Doped ZnO Nanocrystals

共沉淀法制备了稀土镧、铈掺杂的ZnO半导体纳米晶。X射线衍射（XRD）结果表明：掺杂的ZnO纳米晶为六方纤锌矿结构，随掺杂浓度增加ZnO粒径减小。对铈掺杂纳米ZnO，以波长380nm激发，在443nm处出现了半峰宽较窄的强的蓝光发射峰；镧掺杂ZnO纳米晶则为从418-610nm的多峰宽带发射。

Rare earth doped semiconductor nanomaterials have attracted wide interest in recent years. Rare earth ions can improve the electrical and luminescent properties of the matri-materials. For rare earth doped materials, many references reported Er doped systems, but La and Ce doped materials was rarely reported, especially for nanomaterials. This kind study will help to develop new luminescent materials. In this paper, rare earth ions La and Ce doped ZnO nanocrystals were prepared by co-precipitation method. XRD results show that the diffraction peaks of the semiconductor nanocrystals widened and the intensity decreased with the increase of rare earth concentrations in the ZnO nanocrystals which means that the size of the ZnO nanocrystals decreased. The results show the doping of rare earth ions can hold back the growth of ZnO nanocrystals. The La and Ce doped samples have the same results. Strong and narrow blue photoluminescence at 443 nm was observed in 1% Ce doped ZnO nanocrystals excited at 380 nm. It was ascribed to oxide vacancy defect caused by CeO2 new phase. This blue luminescence is important to the preparation of short wave apparatus. The photoluminescence of La ions doped ZnO nanocrystals was a wide peak from 418 nm to 610 nm.