Holey MoS₂ Nanosheets with Photocatalytic Metal Rich Edges by Ambient Electrospray Deposition for Solar Water Disinfection

Abstract

A new method for creating nanopores in single-layer molybdenum disulfide (MoS₂) nanosheets (NSs) by the electrospray deposition of silver ions on a water suspension of the former is introduced. Electrospray-deposited silver ions react with the MoS₂ NSs at the liquid-air interface, resulting in Ag₂S nanoparticles which enter the solution, leaving the NSs with holes of 3-5 nm diameter. Specific reaction with the S of MoS₂ NSs leads to Mo-rich edges. Such Mo-rich defects are highly efficient for the generation of active oxygen species such as H₂O₂ under visible light which causes efficient disinfection of water. 10⁵ times higher efficiency in disinfection for the holey MoS₂ NSs in comparison to normal MoS₂ NSs is shown. Experiments are performed with multiple bacterial strains and a virus strain, demonstrating the utility of the method for practical applications. A conceptual prototype is also presented.