Department of Chemistry and Biochemistry Seminar
- Friday, February 8, 2019 at 3:10pm
- Chemistry & Biochemistry Building, Byker Auditorium - view map
Prof. Scott Warren from UNC, Chapel Hill will present "2D Heterostructures for Energy Storage and Electronics: Exploring the Limits of Weak and Strong Interlayer Interactions."
Abstract: The ability to alter distances between atoms is among the most important tools in materials design. Despite this importance, controlling the interlayer distance in stacks of 2D materials remains a challenge. This talk will present two strategies for controlling this distance, thereby giving rise to several fascinating new classes of materials for electronics and energy storage.
In the first strategy, we self-assemble a monolayer of organic molecules between monolayers of a 2D semiconductor such as MoS2 or phosphorene. The resulting 3D materials are crystalline and have an increased interlayer distance, which gives rise to fascinating and unusual electronic properties. We demonstrate a 3D hybrid made from monolayer MoS2 and organic molecules that retains the desirable properties of monolayer MoS2, such as strong photoluminescence. Even more surprising is that these materials are relatively conductive—thereby allowing the desirable properties of 2D materials to be harnessed in a 3D format that is suitable for electronic devices.
The second strategy introduces a new pathway to reduce interlayer distance. We utilize “2D electrenes,” a new 2D material with an electrical conductivity that rivals silver. 2D electrenes have radically different electronic structures: they have planes of electrons that are physically separated from planes of cations. Using DFT calculations and preliminary experiments, we show that electrenes act as electron donors to 2D metals, semiconductors, and insulators. These materials are the 2D analogs of donor-acceptor systems and have interlayer distances that approach those of covalent or ionic materials. I will describe these structures and their fascinating properties, as well as their role in battery electrodes.
- Department of Chemistry and Biochemistry