The goal of this paper is to present a stable and new formulation route for the synthesis of silver sulfide nanoparticles with stoichiometric Ag₂S composition in aqueous solution. The structural, optical, and morphological properties of Ag₂S nanoparticles were studied by using characterization techniques such as ultraviolet–visible spectroscopy (UV–Vis), transmission electron microscopy and x-ray photoelectron spectroscopy (XPS). From the UV–Vis spectrum, the direct and indirect energy gap values of 3.56 and 1.89 eV were calculated, related to direct and indirect transitions of electrons, as an estimation of bandgaps. Also, an optical band gap shift with respect to bulk bandgap is observed reported in the literature and is related to nanoparticle size decrease. Furthermore, from the high-resolution transmission electron microscopy micrograph an orthorhombic crystallographic structure was determined with lattice parameters 4.77 × 6.92 × 6.88 Å and the nanoparticle surface showed a honeycomb-like interference pattern. Finally, the expected chemical composition was proved by the low- and high-resolution XPS spectra.

本文的目的是为水溶液中合成具有化学计量的Ag ₂ S组成的硫化银纳米颗粒提供一种稳定的新配方途径。Ag ₂的结构，光学和形态学性质通过使用诸如紫外可见光谱（UV-Vis），透射电子显微镜和X射线光电子能谱（XPS）等表征技术研究了S纳米颗粒。根据紫外-可见光谱，计算出与电子的直接和间接跃迁有关的3.56和1.89 eV的直接和间接能隙值，作为带隙的估计。另外，在文献中已经观察到相对于体带隙的光学带隙位移，并且其与纳米颗粒尺寸减小有关。此外，从高分辨率透射电镜显微照片中，以4.77×6.92×6.88Å的晶格参数确定了正交晶的晶体结构，纳米颗粒表面显示出蜂窝状的干涉图案。最后，