单分散的硫化银纳米粒子的一步合成及性质表征

One Step Synthesis and Characterization of Monodispersed Ag_2S Nanoparticles

提出了一个简单的、温和的条件下合成高产量的、均匀的、单分散的硫化银纳米粒子的方法.该化学方法采用硫脲作硫源和稳定剂,室温下与硝酸银反应一步即可获得Ag2S纳米粒子,因而不需采用任何模板和基底.采用X—射线粉末衍射(XRD)、透射电子显微镜(TEM)、X—射线光电子能谱(XPS)以及紫外—可见光谱(UV—Vis)等手段对所合成的产物进行表征.XRD结果表明:产物为单斜相的硫化银,TEM可以看出产物为直径约为50±10nm左右的球状纳米粒子.XPS分析表明:产物中Ag为+1价而S为-2价,它们的原子个数比为Ag∶S=1∶0.489.UV—Vis观察到合成的硫化银纳米粒子在292nm处有特征吸收峰.

A simple, mild method to synthesize high- yield, uniform and monodispersed Ag2S nanoperticles has been presented in this article. Thiourea,used as S- source and the stabilizer,could react with AgNO3 one step to gain Ag2S nanoparticles at room temperature. Thus, no template or substrate is needed. The product was characterized by XRD, TEM, XPS and UV-Vis absorption spectrum. XRD spectrum demonstrates a monoclinic Ag2S; TEM shows the products are sphere - like nanoparticles with average diameter of 50 ± 10 nm. XPS confirms the formation of Ag2S： the valence of Ag, ＋ 1, S, -2; and indicates the sample＇ s surface stoichiometry of Ag： S = 1：0.489. A distinctive absorption peak of Ag2S nanoparticles at 292 nm is observed in the UV- vis absorption spectrum.