摘要
采用共沉淀工艺合成了Yb^(3+)离子和Ho^(3+)离子共掺杂的Lu_2O_3纳米粉体,研究了粉体的斯托克斯(Stokes)和反斯托克斯(Anti-Stokes)发光特性以及煅烧温度对粉体发光性能的影响.在氙灯447.5nm和半导体激光器980nm激发下样品均发射出明亮的绿光,观察到了不同Ho^(3+)离子浓度掺杂的纳米粉体的浓度淬灭现象.发射强度与激发功率的关系表明Anti-Stokes发光是双光子过程,能量转移是主要的上转换机制.Ho^(3+)离子的~5F_4,~5S_2能级在不同波长激发下的衰减时间也证实了浓度淬灭及能量转移现象.
A series of Lu2O3 nanopowders co-doped with Yb^3＋ and Ho^3＋ were synthesized by coprecipitation method. The Yb^3＋ concentration is 1mol% and the Ho^3＋ concentration ranges from 0.5mol% to 10mol%. The Stokes and Anti-Stokes spectroscopic properties of the prepared nanopowders were investigated, together with the relative intensities of Stokes and Anti-Stokes PL spectra dependence on the powders calcined at different temperatures. Strong green emissions were observed under the excitation of 447.5nm （Xenon Lamp） and 980nm （Laser Diode）, respectively. Concentration quenching occurrs with the increase of Ho^3＋ concentration. Power studies reveal that a two-photon process is involved in the Anti-Stokes emissions and the possible upconversion mechanisms are energy transfer from Yb^3＋ to Ho^3＋. Concentration quenching and energy transfer process are confirmed by the decay time of the ^5F4, ^5S2 level under the excitation of different pump wavelength.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第2期383-386,共4页
Journal of Inorganic Materials
基金
国家自然科学基金(50372075)
