Bimetallic
nanoalloys with a wide variety of structures and compositions
have been fabricated through many diverse techniques. Generally, various
steps and chemicals are involved in their fabrication. In this study,
the synthesis of Ag–Bi nanoalloys by femtosecond laser irradiation
of an inorganic oxide Ag
2
WO
4
/NaBiO
3
target without any chemicals like reducing agents or solvent is
presented. The interaction between these materials and the ultrashort
pulse of light allows the migration of Ag and Bi atoms from the crystal
lattice to the particles surfaces and then to the plasma plume, where
the reduction of the positively charged Ag and Bi species in their
respective metallic species takes place. Subsequently, the controlled
nucleation and growth of the Ag–Bi alloyed nanoparticles occurs
in situ during the irradiation process in air. Although at the bulk
level, these elements are highly immiscible, it was experimentally
demonstrated that at nanoscale, the Ag–Bi nanoalloy can assume
a randomly mixed structure with up to 6 ± 1 atom % of Bi solubilized
into the face-centered cubic structure of Ag. Furthermore, the Ag–Bi
binary system possesses high antibacterial activity against
Staphylococcus aureus
(methicillin-resistant and
methicilin-susceptible), which is interesting for potential antimicrobial
applications, consequently increasing their range of applicability.
The present results provide potential insights into the structures
formed by the Ag–Bi systems at the nanoscale and reveal a new
processing method where complex inorganic oxides can be used as precursors
for the controlled synthesis of alloyed bimetallic nanoparticles.