Chemistry Department Seminar: Tenure Track Candidate
"The Mechanics and Chemistry of 2D Material Bubbles"
When two-dimensional (2D) materials are transferred onto a supporting substrate, matter trapped at the interface can spontaneously coalesce to form bubbles with nanometer-scale dimensions. 2D material bubbles have exciting applications as nanoscale chemical reactors and as tools to prescribe localized deformations in 2D materials. However, strategies to deterministically control the properties and behavior of these bubbles, such as the strain level in the 2D material, or the chemical content of the trapped matter, remain unclear. This is due to a lack of fundamental understanding of the chemical composition of the bubble, the adhesive behavior of the 2D material/substrate interface, and the nanoscale mechanical behavior of 2D materials. To address this knowledge gap, we first explore the physics that governs the formation of these bubbles using atomic force microscopy and a simple scaling law to describe the thermodynamics of their formation. This scaling law highlights the importance of the surface energy of the confined matter and motivates further efforts to understand the bubble chemistry. We use time-of-flight secondary ion mass spectrometry to study the chemical composition of trapped matter and demonstrate how foreign chemicals can be introduced inside 2D material bubbles by controlling chemicals vaporized in the ambient fabrication environment.
*This seminar counts towards the chemistry major seminar attendance requirement.