聚电解质/硫化镉薄膜的层-层组装及其光谱分析

以六偏磷酸钠为稳定剂,采用硝酸镉和硫化钠合成了硫化镉纳米颗粒,利用层-层组装技术制备了聚电解质与硫化镉胶体的复合薄膜.吸收光谱显示,硫化镉胶体的吸收带边相对其体相有明显蓝移,并可观察到激子吸收峰,显示出量子尺寸效应.复合薄膜的荧光光谱上出现2个发光带,随着薄膜的组装层数的增加,复合薄膜的带带跃迁发光和表面态发光都相应减弱.

Layer-by-Layer Assembly and Spectrum Study on Polyelectrolyte/CdS Nanoparticle Composite Films

Colloidal cadmium sulfide (CdS) stabilized with (NaPO3)6 was prepared from Cd(NO3)2 and Na2S. Poly(dimeth ylammonium chloride) was used to fabricate polyelectrolyte/CdS multilayer composite films via the layer-by-layer self-assembly technique. The colloidal CdS was characterized using a UV-visible spectrophotometer and a transmission electron microscope, and the composite multilayer thin films were characterized using the UV-visible spectrophotometer and a fluorescence spectrophotometer. The onset absorption of the colloid is at 465 nm with an obvious blue shift relative to that of bulk CdS, and an absorption shoulder around 400 nm can be observed on the absorption spectrum. Two emission peaks can be seen on the emission spectra of the composite films. The experimental results show that the photoluminescence behaviors of the composite films subject to the dipping cycle numbers or the film thickness.