Generation of Vanadium Oxide Quantum Dots with Distinct Fluorescence and Antibacterial Activity via a Room-Temperature Agitation Strategy

Vanadium oxide (VOx) nanomaterials have been attracting great attention recently due to their outstanding physicochemical properties. Engineering VOx into quantum dots (QDs) should bring new properties and potential for applications, but has not been reported until now. Meanwhile, the shortcomings in QDs synthesis such as needing high temperature and expensive instruments still need to be overcome. Herein, VO(x)QDs were generated via a simple ultrasonic and agitation strategy at room temperature using DMSO as both solvent and exfoliation agent. The VOx QDs exhibited blue fluorescence under 365 nm ultraviolet irradiation. They were with good monodispersion, narrow size distribution and average particle size of 3.3 +/- 0.3 nm. The VO(x)QDs can be used as a competitive fluorescent sensing probe for label-free specific detection of Fe3+ and PPi based on the ON-OFF or ON-OFF-ON fluorescent principle, respectively. Moreover, the antibacterial activity of the as-prepared VO(x)QDs was found, which could damage the cell membrane and inhibit the bacterial growth of both Gram (+) (Staphylococcus aureus) and Gram (-) (Escherichia coli) bacteria, respectively.