摘要
本文系统地测量纳米氮化硅粉体和块材的红外吸收谱,并与常规氮化硅的红外吸收谱进行比较,观察到纳米氮化硅粉体在横光学模频率(ω_(T0))附近的吸收峰存在蓝移、纳米氮化硅块材在ω_(T0)频率附近存在宽化现象。由于纳米材料的小尺寸效应,纳米粒子的表面能很大,巨大的表面能使得粒子内的原子间距发生变化,产生蓝移。纳米材料的界面效应使得界面原子间距存在一定分布,导致宽化。当颗粒长大,原子间距趋于正常态,这种现象消失。
There exist distinct differences between the infrared absorption spectra of nanometer-sized silicon nitride and conventional silicon nitride. Compared with conventional silicon nitride, for the nanometersized silicon nitride powder, its absorption peak exhibits 'blue shift' at ω_(T0), for the nanometer-sized silicon nitride bulk, its absorption exhibits 'widezation'. The 'blue shift' of nanometer-sized silicon nitride was ascribed to the effect of small size, i. e., the large surface energy can lead the interatomic space to decrease. The 'widezation' of the nanometer-sized silicon nitride bulk was owe to the interface effect, which can lead the wide distribution of the interatomic space in the interface. With grains size growing, the interatomic space tended to the normal value and the novel phenomenon of nanometer-sized silicon nitride disappeared.
出处
《中国科学院研究生院学报》
CAS
CSCD
1993年第4期355-359,共5页
Journal of the Graduate School of the Chinese Academy of Sciences
关键词
红外吸收光谱
蓝移
宽化
氮化硅
nanometer-sized material
infrared absorption9 blue shift
widezation
