Upshift of the d Band Center toward the Fermi Level for Promoting Silver Ion Release, Bacteria Inactivation, and Wound Healing of Alloy Silver Nanoparticles

Silver (Ag)-based nanoparticles (NPs) with a high potential of Ag+ release have been known to be capable of promoting bacteria inactivation and the wound healing process; however, keeping a steady flux of high levels of Ag+ in Ag-based NPs is still challenging. Herein, a novel strategy in terms of altering the intrinsic electronic structure of Ag NPs was attempted to facilitate Ag oxidation and boost the Ag+ flux, as results of improved antibacterial and wound healing performance of Ag NPs. Gold (Au), platinum (Pt), and palladium (Pd) were doped into Ag NPs to tune their d band centers to upshift toward the Fermi level, and the formed Pd–Ag alloy NPs showed the largest shift, followed by Pt–Ag and Au–Ag NPs, as determined by density function theory calculation and ultraviolet photoemission spectroscopy measurement. Further X-ray photoelectron spectroscopy analysis indicates that a larger upshift could induce less electron filling in the antibonding orbital and a higher Ag oxidation level, leading to the m...