Transition metal dichalcogenide quantum dots (TMD QDs) enhance the optical and electronic properties of larger 2D nanosheet TMDs. Wider use of QDs in catalytic and biomedical applications has been constrained by the complexity of their synthesis.

The top-down approach used to produce TMD nanomaterials involves processing mineral ores to the nanometerMolybdenite QDs in aqueous solution (left) and under ultrahigh magnification (right). Source: National University of SingaporeMolybdenite QDs in aqueous solution (left) and under ultrahigh magnification (right). Source: National University of Singapore scale by physical or chemical treatment. This method is low in scalability and cost-intensive, as separating nanomaterial fragments by size requires multiple purification processes.

A new process devised at the National University of Singapore yields TMD QDs of a specific size in a scalable and less costly bottom-up approach that also allows material properties to be engineered for different applications. Transition metal oxides or chlorides are reacted with halogen precursors under mild aqueous and room temperature conditions.

The researchers fabricated seven TMD QDs with the process, which also enabled modification of electronic and optical properties as desired. Molybdenite QDs were also synthesized to demonstrate proof-of-concept as effective photodynamic agents to kill cancer cells. Additional uses of TMD QDs to be explored include applications in next-generation TV and electronic device screens, advanced electronics components and solar cells.

The research is published in Nature Communications.

To contact the author of this article, email shimmelstein@globalspec.com