CdS半导体超微粒样品光谱性质的研究

Optical Spectroscopy Properties of CdS Semiconductor Ultrafine Particles

纳米尺度的半导体超微粒在线性和非线性光学方面表现出来的奇特性质使其成为研究和开发新的功能材料的热点。成键为 S、P轨道的 - 族金属硫化物半导体 ,电子结构和晶体结构均较为简单 ,结晶性能好 -界面无序结构少 ,在纳米尺度上其结构仍与体相材料近似 ,因此 ,成为研究量子尺寸效应的理想材料。本文对采用化学微乳液法合成的 Cd S半导体超微粒的光谱性质进行了研究 ,实验结果显示 ,Cd S超微粒样品的吸收光谱的带边与体相相比发生了蓝移 ;从吸收光谱中可以看到 ,Cd S超微粒样品的吸收边随粒径减少而向短波方向移动。拉曼光谱的电子—— L O声子耦合在粒子尺寸 2 .4- 2 .

The optical and non linear optical properties of CdS semiconductor ultrafine particles are reported. Both the energy band and the crystal structure of Ⅱ Ⅵ metal chalcogenides with s, p bonding orbitals are simple. They are easy to crystallized and their crystals contain small amount of interfacial disorder. These properties of bulk Ⅱ Ⅵ metal chalcogenides are retained in the chalcogenides in the nanometer range, making the nanoscale chalcogenide an ideal material for the study of quantum size effect. The CdS semiconductor ultrafine particles were synthesized by using organometallic reagents in inverse micellar solution. Optical measurements show the absorption edge of CdS ultrafine particles is blue shifted relative to the absorption edge of bulk CdS. Furthermore, the coupling between electron and LO phonon in the Raman Sectra is not dependent on the size of the particles in the range of 2.4 to 2.9nm.