含镧的Bi_2Te_3基化合物的溶剂热合成及微观结构  

Solvothermal Synthesis and Microstructures of Bi_2Te_3 Based Compounds Containing Lanthanum

作　　者：张艳华[1] 赵新兵[1] 吉晓华[1] 

机构地区：[1]浙江大学硅材料国家重点实验室

出　　处：《中国稀土学报》2004年第1期104-107,共4页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金资助项目(50171064);"863计划"资助项目(2002AA302406)

摘　　要：以BiCl3,LaCl3和Te粉为原料,用溶剂热合成法制备了含稀土元素的单相LaxBi4Te6(x≤1)热电材料纳米粉末。研究发现,三元化合物LaxBi4Te6具有与二元Bi2Te3化合物相同的晶体结构和相似的晶格常数。LaxBi4Te6中的La含量随合成温度升高而增加,但与反应时间没有显著关系。LaxBi4Te6合成粉末的颗粒尺寸在30nm左右,并且几乎与反应温度和反应时间没有关系。在120℃合成的粉末基本上为不规则多面体形状,在150℃及以上温度合成的粉末则趋向于薄片状,并存在一些直径在50～80nm之间的纳米管。Rare-earth element-contained thermoelectric La_xBi_4Te_6 (x≤1) nano-sized powders have been prepared by solvothermal synthesis from BiCl_3, LaCl_3 and pure telluride powder. It is found that the ternary compounds La_xBi_4Te_6 have the same crystal structure and similar lattice parameters as binary Bi_2Te_3. The lanthanum contents in La_xBi_4Te_6 increase with the synthesis temperature and are independent on the reaction time. The average size of synthesized La_xBi_4Te_6 powders is about 30 nm, which is not influenced by the reaction temperature and time. The powders synthesized at 120 ℃ have an irregular polyhedral morphology, while those synthesized at 150 ℃ or above tend to be formed in thin sheets. Nano-tubes with a diameter between 50 and 80 nm have been found in the powders synthesized at 150 ℃ or above.

关 键 词：金属功能材料 溶剂热合成 BI2TE3 热电材料 稀土 

分 类 号：TN304[电子电信—物理电子学]