Molybdenum disulfide (MoS2) nanostructures are layered 2D transition metal dichalcogenide with unique physical, chemical, and biological properties. These properties can further be optimized during the synthesis process by introducing atomic defects within the layered nanostructure of MoS2. Herein, MoS2nanostructure with varying defect density is synthesized and highly hydrophilic MoS2nanostructure is shown to be obtained by increasing the atomic defects. This hydrophilic MoS2nanostructure is further incorporated within electrospun polyacrylonitrile (PAN) nanofibers to improve the physical and chemical properties. Uniform distribution of MoS2nanoassemblies is observed within the PAN nanofibers. Significant increase in electrical conductivity, thermal stability, and mechanical strength of PAN nanofibers are obtained due to MoS2addition. Interestingly, the addition of MoS2nanostructure resulted in enhanced protein adsorption as well as cytocompatibility of these hybrid PAN‐MoS2nanofibers due to hydrophilic characteristics of MoS2nanoassemblies. It is expected that these hybrid PAN‐MoS2nanofibers can potentially be used for a variety of biomedical applications including drug delivery, tissue engineering, and biosensing.
Surface acoustic waves (SAWs) propagate along solid-air, solid-liquid, and solid-solid interfaces. Their characteristics depend on the elastic properties of the solid. Combining transmission electron microscopy (TEM) experiments with molecular dynamics (MD) simulations, we probe atomic environments around intrinsic defects that generate SAWs in vertically stacked two-dimensional (2D) bilayers of MoS2. Our joint experimental-simulation study provides insights into SAW-induced structural and dynamical changes and thermomechanical responses of MoS2bilayers. Using MD simulations, we compute mechanical properties from the SAW velocity and thermal conductivity from thermal diffusion of SAWs. The results for Young’s modulus and thermal conductivity of an MoS2monolayer are in good agreement with experiments. The presence of defects, such as nanopores which generate SAWs, reduces the thermal conductivity of 2D-MoS2by an order of magnitude. We also observe dramatic changes in moiré patterns, phonon focusing, and cuspidal structures on 2D-MoS2layers.
more » « less- PAR ID:
- 10518627
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Computational Materials
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2057-3960
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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