真空热蒸发法制备CdS纳米带及其光学性质

Synthesis and Mechanism of CdS Nanobelts by Vacuum Thermal Evaporation Method

在常规真空镀膜仪中,我们首创了一种利用真空热蒸发原理在催化剂Bi的辅助下制备一维CdS纳米带的方法.X射线衍射(XRD)和X射线能量色散谱(EDX)实验证明所得纳米带为纯的六方纤锌矿型CdS结构.扫描电子显微镜(SEM)观察到CdS纳米带在较大范围内具有非常均匀的带宽.光致发光谱发现CdS纳米带有两个发光带.经分析推测CdS纳米带的生长机理为:生长前期为气-液-固(VLS)机制占主导地位,而气-固(VS)机制在纳米带的形成过程和生长的后期起决定作用.

One dimensional CdS nanobelts were synthesized by using vacuum thermal evaporation method which was operated by the normal vacuum evaporator（VE） for the first time. X-ray diffractiion（XRD） and Energy Dispersive X-ray Detector （EDX） demonstrated that the products were composed of pure hexagonal phase CdS. The scanning electron microscopy （SEM） revealed that the CdS nanobelts had uniform width in a large scale area. In room-temperature the photoluminescence reveals two peaks. It was found that the growth mechanism of CdS nanobelts at the first stage was the conventional Vapor-Liquid-Solid （VLS） mechanism, whereas the Vapor-Solid （VS） process played a crucial role in the later growth of the nanobelts.