不同晶粒尺寸SnO_2纳米粒子的拉曼光谱研究  

Raman study of SnO_2 nanograins under different annealing temperature

作　　者：丁硕[1] 刘玉龙[1] 萧季驹[2] 

机构地区：[1]中国科学院物理研究所,北京100080 [2]香港城市大学物理与材料科学系

出　　处：《物理学报》2005年第9期4416-4421,共6页Acta Physica Sinica

基　　金：国家重点基础研究发展规划项目(批准号:2002CB713803)资助的课题.~~

摘　　要：对晶粒尺寸在4—80nm范围的纯SnO2纳米颗粒进行了拉曼散射研究.除了SnO2本征拉曼振动峰外,还有几个新的拉曼振动峰和波长在700nm左右的一个发光很强而且峰宽很大的荧光峰被观察到.结果所示,当纳米颗粒尺寸减小时,纳米SnO2颗粒的体相特征拉曼峰变弱,而由缺陷,表面和颗粒尺寸引起的相关效应呈强势.晶粒尺寸在20nm左右是引起体相拉曼光谱变化的临界尺寸.晶粒尺寸在20nm以下,其体相拉曼峰的发生宽化和峰位移动,以及分别出现在位于571cm-1的表面振动峰,位于351cm-1处的界面峰和与表面吸附水分子及氢氧基团的N系列拉曼峰是纳米SnO颗粒的主要特征.这些结果反映了纳米颗粒的微结构变化与颗粒尺寸和表面效应以及它们之间相互作用的信息.SnO2 nano-crystalline grains with sizes in the range of 4-80 nm are systematically investigated using Raman spectroscopy. Besides SnO2 fundamental-frequency modes, a few weak Raman modes and a very strong and broad photoluminescence peak at about 700 nm can be observed. Our results show that bulk properties of nano-SnO2 diminish but the defect-, surface-, and size- related features display as grain size decreases. A critical size that divides respective predominance is determined to be about 20 nm. Bulk spectra with spectroscopic line broadening and position shifting, a surface mode and interface mode around 571 cm^-1 and 351 cm^-1, as well as the O-H vibration modes of the water molecules in SnO2 nanograins are characteristics of Raman spectra of nano-SnO2 with grain size below 20 nm. They are related to the microstructure change of the nanograins, i.e. they reflect the change of grain size, surface, and the interaction between nanograins.

关 键 词：纳米SNO2 拉曼光谱 荧光光谱 水分子的吸附 拉曼散射 晶粒尺寸 纳米粒子 光谱研究 纳米颗粒 表面振动 颗粒尺寸 微结构变化 

分 类 号：O572.2[理学—粒子物理与原子核物理]