Simultaneous Fabrication and Functionalization of Nanoparticles of 2D Materials with Hybrid Optical Properties

A general, rapid technique is introduced to simultaneously fabricate and functionalize nanoparticles of 2D materials. A femtosecond laser is used to irradiate flakes of 2D materials in an ethanol-containing solvent. The highly energetic laser pulses exfoliate and cleave the flakes into nanosheets with diameters of approximate to 3 nm and simultaneously dissociate the solvent molecules. The dissociated carbon and oxygen atoms bond with the freshly cleaved 2D nanoparticles to satisfy edge sites, resulting in the formation of hybrid 2D nanoparticles that contain graphene-like carbon domains as well as the host material. The technique is demonstrated for molybdenum disulfide (MoS2), tungsten disulfide (WS2), and boron nitride (BN) flakes. Notably, the hybrid nanoparticles are formed in as little as 20 min without toxic or corrosive chemicals and are multifunctional. Photoluminescence and absorption owing to both the carbon domains and host 2D material (MoS2, WS2, or BN) are observed. This novel hybrid optical behavior makes these materials promising for emerging nanoelectronic and nanophotonic applications.