Thermal Engineering of Nanostructured Materials

Motivation. Thermal transport in micro/nano devices is at the forefront of electronics research thanks to their ever increased miniaturization, operating frequencies and power dissipation densities. The performance of modern electronic devices can be profoundly affected by the aggressive thermal conditions imposed upon them. Therefore, investigating the heat transfer mechanisms and thermal tunability of the constituent nanostructured materials of these devices is paramount to increasing their reliability, efficiency and lifetime.

2D Graphene
2D Graphene/h-BN heterostructure
Buckled and Puckered monolayers
Buckled (β-phase) and Puckered (α-phase) group-VA monolayers

Research Activities. ATOMS Lab research in this field contributes to elucidating the physics of thermal energy carriers (phonons) in nanostructured materials (e.g., thin films, 2D materials, and heterostructures) and developing multiscale, hierarchical modelling methodologies that transfer physically-accurate atomistic-level information to macroscale models. Over the past 10+ years, we have focused on the thermal characterization and tunability of the thermal conductivity of novel 2D nanomaterials via interface phonon scattering and strain engineering using first-principles and molecular dynamics simulations. These materials include monolayers and heterostructures of graphene, molybdenum disulfide, hexagonal boron nitride, phosphorene, arsenene, and C3N. 

C3N lattice structure
C3N lattice structure
C3N thermal response
C3N thermal response to tensile strain

Sub-Continuum Transport Phenomena in Metal-ion Batteries

Motivation. Lithium-ion battery (LIB) technologies have advanced significantly in recent years, becoming the most widely used energy storage technology in electronic devices, electric vehicles, and stationary energy storage for renewables. However, next-generation batteries are required to be of even higher energy density, light-weight, long-lasting, easier-to-manufacture, and less susceptible to temperature-induced degradation phenomena. This requires a radical new approach for electrochemical and thermal design with a focus on post-lithium battery technologies based on abundant materials on the Earth’s crust.

Research Activities. Leveraging our extensive expertise in nanoscale thermal transport, we are investigating the thermal and electrochemical performance of 2D heterostructures as electrodes for post-lithium metal-ion batteries using first-principles, machine learning, and molecular dynamics simulations. This research involves multiscale hierarchical modelling methodologies covering all relevant physical domains, time, and length scales for metal-ion batteries. Leveraged by state-of-the-art machine learning algorithms, these hierarchical modelling methodologies integrate simulations from atomistic models of the nanostructured electrodes with Density Functional Theory (DFT) and Molecular Dynamics (MD) into reduced-order thermo-electrochemical models of the macroscale battery architecture.

Diffusion of a Li ion
Diffusion of a Li ion on BlueP/C3N Heterostructure
Charge density difference for an absorbed Li ion
Charge density difference for an absorbed Li ion

ATOMS Laboratory is conducting multidisciplinary collaborative research with the Laboratory for Strategic Materials to develop an innovative modelling-experimental framework for material discovery combining thermo-electrochemical hierarchical modelling of batteries with state-of-the-art material synthesis processes and characterization techniques.