September 24, 2014

Speaker: Chandra Veer Singh, Department of Materials Science and Engineering, University of Toronto

Title: Atomistic Insights Into Mechanical Behaviour of Two-Dimensional Materials

Abstract: Since isolating graphene, multiple two-dimensional materials (2DMs) have been synthesized experimentally. Many more have been theorized – with intriguing chemical, electronic, thermal and mechanical properties that expand the boundaries of existing structure-property space.

In a short time span, significant research knowledge has already been amassed regarding their chemical and electronic properties. However, their mechanical properties have just begun to be explored. For any device to function well, be it for electronic or energy storage purpose, material needs to be reliable and stable mechanically; if it fails prematurely, it is of no use. The tremendous mechanical properties of 2DMs mean they can also serve as reinforcing agents for next generation materials for automotive and aerospace applications.

In this talk, we would describe our recent investigations that aim to understand the fundamental mechanical behaviour of 2D materials using atomistic simulations. First, we would describe thermally activated failure initiation in graphene with point defects and grain boundaries; and how this analysis brings simulation predictions much closer to experimental data. Then, we will present the first-time measurement of the intrinsic strength of monolayer graphene oxide supported by first principles calculations. This work will also serve as an example of how we can combine experimental testing with atomistic modeling techniques to provide a more coherent and in-depth understanding. Finally, ongoing studies on theoretical properties of two dimensional transition metal dichalcogenide (TMD) nanosheets will be described.