P(S-SS)/CdS核壳粒子的制备与表征

采用超声辐照乳液聚合得到聚(苯乙烯-苯乙烯磺酸钠)(P(S-SS))乳胶粒,用直接沉淀法在乳胶粒表面原位生成硫化镉(CdS)纳米粒子,得到P(S-SS)/CdS核壳粒子。用元素分析和XPS研究了共聚物的组成及磺酸基(-SO3-)的分布,结果表明,-SO3-主要分布在乳胶粒表面,有利于CdS纳米粒子在乳胶粒表面的沉积。用XRD、TEM及UV-v is表征了共聚物乳胶粒及P(S-SS)/CdS核壳粒子的结构及CdS的量子效应。结果表明,所制备的CdS纳米粒子为六方晶型,平均粒径为6 nm,在P(S-SS)乳胶粒外层形成多层包覆,P(S-SS)/CdS核壳粒子平均粒径为70 nm,CdS纳米粒子表现出明显的量子尺寸效应。

THE PREPARATION AND CHARACTERIZATION OF P (S-SS)/CdS Core-Shell Particles

P(styrene-co-sodium styrene sulfonate)(P(S-SS)) latex with small particle size about 40nm and narrow size distribution were prepared through ultrasonically initiated emulsion polymerization.Then,CdS nanoparticles in-situ formed on the surface of P(S-SS) latex,resulting in P(S-SS)/CdS core-shell nanocomposites.Element analysis and XPS results show that the sulfonate group mainly arranges on the surface of copolymer latex,which benefits the formation of CdS nanoparticles on the surface of P(S-SS) latex.XRD patterns confirm the formation of about 6nm hexagonal CdS nanocrystal.TEM suggests that the average particle size of the resulted P(S-SS)/CdS core-shell nanocomposites is around 70 nm.UV spectra indicates that the prepared CdS nanoparticles exhibit clear optical absorption and blue shift compared with the bulk CdS.