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 (MoS 2 ) 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 MoS 2 NSs at the liquid–air interface, resulting in Ag 2 S nanoparticles which enter the solution, leaving the NSs with holes of 3–5 nm diameter. Specific reaction with the S of MoS 2 NSs leads to Mo‐rich edges. Such Mo‐rich defects are highly efficient for the generation of active oxygen species such as H 2 O 2 under visible light which causes efficient disinfection of water. 10 5 times higher efficiency in disinfection for the holey MoS 2 NSs in comparison to normal MoS 2 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.

Ambient microdroplet annealing of nanoparticles

“…3,[29][30][31] Surprisingly, microdroplet chemistry through ambient electrospray converts irregular particles into a superstructure of uniform particles within a fraction of a second. [6][7][8][9][10] Optimizing microdroplet annealing…”

“…[6][7][8] This synthetic method can be tuned with the application of electrical potential and can lead to assemblies of nanomaterials and a viable method for forming 1D structures with potential applications was demonstrated. 7 Materials science with charged microdroplets can produce nanoholes on 2D materials 9 and metallic thin films on liquid surfaces 10 .…”

Solar‐Driven Photocatalytic Disinfection Over 2D Semiconductors: The Generation and Effects of Reactive Oxygen Species

“…The introduction of Mo‐rich defects into holey MoS 2 nanosheets was highly efficient for the generation of H 2 O 2 species. [ 172 ] The electrospray‐deposited silver ions reacted with MoS 2 at the liquid–air interface, drilling holes in MoS 2 sheets and leaving the Mo‐rich defects. Due to the high catalytic activity of the defects, the holy MoS 2 showed a rapid generation of H 2 O 2 which in turn disinfected the microbial contamination in water.…”

Challenges and Directions for Green Chemical Engineering—Role of Nanoscale Materials

“…85 Nanopores made in MoS2 nanosheets can produce H2O2 efficiently using visible light, causing disinfection of flowing water. 86 While new technologies for clean water are essential, contaminants have to be detected and measured quantitatively at ultra-trace levels. Many nanostructures can effectively perform these functions 87,88 , making affordable sensing and removal possible.…”