室温合成硫化银纳米粒子及其X射线光电子能谱表征

在常温常压下制备了硫化银纳米粒子，选用廉价的氧化银和硫粉为原料，采用多聚甲醛为还原剂，并在乙二胺体系中完成了反应。所得产物用X射线光电子能谱、X射线粉末衍射和透射电镜进行了表征。X射线粉末衍射表明：产物为单斜相的硫化银；透射电子显微镜表明：产物为直径约为100nm的棒状纳米粒子，其对应的电子衍射斑点可以指标成(120)和(303)，说明产物的结晶较好；X射线光电子能谱分析表明：产物中Ag属 1价而S属-2价，它们的原子个数比为Ag：S=1：0．453。对比实验表明：多聚甲醛和无水乙二胺都起了很关键的作用；多聚甲醛起了多重作用，它既是溶剂，又是中和剂，用以除去反应的副产物多个点-甲酸，从而加速了反应的进行。

Synthesis of Ag2S Nanoparticles at Room Temperature and Their Characterization with XPS

Nanocrystalline silver sulfide was successfully synthesized at room temperature and ambient pressure via a novel, safe, convenient and inexpensive redox reaction, using silver oxide, sulfur and polyformaldehyde as reactants and ethylenediamine as solvent. The products were characterized with XPS, XRD and TEM. XRD spectrum demonstrates a monoclinic Ag2S; TEM shows the products are rod-like nanoparticles with average diameter of 100 nm, its corresponding SAED reveals clear diffraction spots indexed as (120) and (303); XPS confirms the formation of Ag2S and indicates the sample's surface stoichiometry of Ag:S=1:0.453. The control experiments show polyformaldehyde and ethylenediamine are both important in the formation of products. Ethylenediamine accelerates the reactions via dissolving silver oxide and sulfur and neutralizing the by-product formic acid.