Facile Monomer Phase Exfoliation and Thin Film Processing of Layered Transition Metal Dichalcogenides: 2D Material Nanocomposites for High-Performance Optical Coatings

We demonstrate the facile exfoliation of transition metal dichalcogenides (TMDCs) directly in neat acrylate monomers resulting in readily processable stable colloidal dispersions─bypassing conventional methodologies that require process-limiting solvents and nanomaterial ligand functionalization. As such, we likewise demonstrate the controlled ease of fabricating polymer/TMDC nanocomposite thin films via free radical and anionic polymerization with minimal to no post-exfoliation processing. Our polymer/TMDC nanocomposite films offer tailored effective optical properties (i.e., effective refractive index, n eff, and effective extinction coefficient, k eff ) simply by adjusting the exfoliated TMDC colloidal dispersion concentration prior to thin film fabrication. Our nanocomposite films yield appealingly large changes in effective optical constants of up to ∼Δ2.2 for n eff and ∼Δ1.8 for k eff (as compared to neat polymer), which contrast is necessary to develop application-relevant optical coating systems. The direct exfoliation of TMDCs in neat monomers and the ease of thin film nanocomposite processing present alternative approaches for high-performance optical coating development with utility in sensing, imaging, and energy harvesting.