Wang Wei, Lu Wensheng, Jiang Long
Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
J Colloid Interface Sci. 2009 Oct 1;338(1):270-5. doi: 10.1016/j.jcis.2009.06.010. Epub 2009 Jun 7.
A simple method for fabricating Ag/AgCl hollow spheres was developed by using a multi-amine head surfactant C18N3 as a soft template. After adding AgNO(3) to micelles of C18N3 dispersed in HCl solution, Ag/AgCl hollow spheres were formed with diameters ranging from 100 nm to 1200 nm which were a function of aging time. The mechanical strength of the formed spheres was found to be very good, probably due to the uniquely structured C18N3 surfactant as well as the reinforcement effect of Ag/AgCl on the NH(2) terminal groups. The active species on the surfaces of hollow spheres, Ag(+) and Cl(-), remained almost unchanged when exposed to natural daylight for more than 1 year, showing a very good stability against light and environmental reduction. However, the obtained Ag+ species on the surface could be transformed into Ag(0) quickly with high yield (ca. 90%) under UV light irradiation. The transfer process was studied by EDX spectra at different irradiation times. Thus the Ag/AgCl hollow spheres may serve as useful precursors for many other noble metallic hollow spheres because Ag could be replaced by other noble metals such as Au and Pt with the aid of the galvanic replacement reaction.
通过使用多胺头表面活性剂C18N3作为软模板，开发了一种制备Ag/AgCl空心球的简单方法。将AgNO3添加到分散在HCl溶液中的C18N3胶束中后，形成了直径范围为100nm至1200nm的Ag/AgCl空心球，其直径是老化时间的函数。发现所形成球体的机械强度非常好，这可能归因于独特结构的C18N3表面活性剂以及Ag/AgCl对NH2端基的增强作用。当暴露在自然日光下超过1年时，空心球表面的活性物种Ag+和Cl-几乎保持不变，显示出对光和环境还原具有非常好的稳定性。然而，在紫外光照射下，表面获得的Ag+物种可以快速高产率（约90%）转化为Ag(0)。通过不同照射时间的EDX光谱研究了转移过程。因此，由于借助于电化置换反应Ag可以被其他贵金属如Au和Pt替代，Ag/AgCl空心球可以作为许多其他贵金属空心球的有用前驱体。
