Can Silver Be Alloyed with Bismuth on Nanoscale? An Optical and Structural Approach

The bulk AgBi alloy system comprises a wide forbidden range of Ag solubility limited to a negligible molar fraction. In this contribution it is unambiguously demonstrated that Ag and Bi, elements with various in-common potential applications, can be alloyed on nanoscale, which is hugely different from the bulk form. These nanostructured Ag–Bi alloys are prepared by a mechano-chemistry pathway under normal conditions and without large amounts of solvents. The characterization of the nanoparticles by combination of UV–visible absorption and Raman spectroscopies as well as SEM, HAADF-STEM, XRD, and DSC lead to the finding of these sui generis nanoalloys and the unprecedented proposal of a predominantly atomic mixed alloyed structure for the Ag x Bi1–x (0.1 ≤ x ≤ 0.5) clusters. This arrangement allows the coexistence of bulk-like lattices of zerovalent Bi and Ag. These resulting nanoparticles can effectively degrade NO; however, they are rapidly oxidized.