摘要
研究以草酸和氨水作为沉淀剂制备BaHfO3:Ce纳米粉体的工艺。用XRD、TEM等测试技术,分析不同沉淀剂对粉体合成中的物相变化、形貌及Ce3+掺杂量对粉体激发光谱和发射光谱的影响。结果表明:以氨水做沉淀剂在900℃煅烧2h合成的BaHfO3:Ce粉体形貌近似球形,平均粒径约15nm。用草酸做沉淀剂、合成温度为1000℃时其粉体形貌呈多边形,粒径约60nm。微量Ce3+的掺杂不改变BaHfO3的晶体结构。Ce3+掺杂量(摩尔分数)为0.3%的BaHfO3发射光谱相对峰强度最高,当Ce3+掺杂量大于0.3%时出现浓度淬灭现象。粉体的激发和发射光谱均存在较宽的谱带,主要由激活Ce3+的5d→2F5/2和5d→2F7/2宽带能级跃迁产生。
The processing technology of Ce doped-BaHfO3 nano-powders that is prepared by co-precipitation （with oxalic acid and ammonia as the precipitant, respectively） was investigated. XRD and TEM were employed to analyze the effects of different precipitates on the phase change, morphologies of powders and influences of Ce^3＋ dopant content on the excitation and emission spectra of powders. The results show that spherical BaHfO3：Ce nano-powders are synthesized only at 900℃ for 2 h and the average diameter is about 15 nm with ammonia as precipitant. But using oxalic acid as precipitant, the powders have polygonal morphology after calcining at 1 000 ~C for 2 h and the average diameter is about 60 nm. Minor Ce^3＋ has no effect on the crystal structure. The relative intensity of photoluminescence peak has the maximum value when the Ce^3＋dopant content is 0.3% （mole fraction）. The concentration quench occurs when the Ce^3＋ dopant content exceeds 0.3%. The emission character is resulted from 5d→^2F5/2 and 5d→^2F7/2 transitions of Ce^3＋ and both the excitation and emission spectra are wide band.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2008年第8期1492-1497,共6页
The Chinese Journal of Nonferrous Metals
基金
辽宁省科技攻关计划资助项目(2005222009)
辽宁省自然科学基金资助项目(20062001)
作者简介
通讯作者：马伟民，教授，博士；电话：024-81358863：E-mail：maweimin56@163．com
