Interview with James Loomis

I am James Loomis, a PhD candidate in the Department of Mechanical Engineering at the University of Louisville. My advisor is Dr. Balaji Panchapakesan whom we all like to call "Baloo".

Studying photomechanical actuation gives me another building block that can be applied towards future engineering challenges. Photomechanically responsive materials can be utilized to create lightweight and highly responsive actuators, and have already shown a variety of possible applications, including photonic switches, robotics, plastic motors, and adaptive micro-mirrors.

Our latest paper reports graphene nanoplatelet based photomechanical actuators. For some materials, energy from an external source can trigger changes in the internal equilibrium state of the structure leading to mechanical responses much larger than the initial input. The ability to unlock this internal work is key for the realization of future solid state actuator technologies. Graphene is a highly interesting material and is the mother of all graphitic forms including nanotubes and buckyballs. Building light driven actuators based on graphene sheets could bring advantages such as light weight, high strength as well as extraordinary photomechanical actuation of 7-9 MPa/W. Such actuators as reported here could be useful in building robotic missions to Mars and asteroids with the ability to scavenge energy and convert that into mechanical motion, electricity and thermal energy.

The next aspect of this research involves investigating dimensional effects of carbon-based photomechanical actuation. From there, our plans include determining whether mixed dimensional systems, such as graphene and carbon nanotubes, could potentially create enhanced photomechanical actuation in composites. We are curious whether differences in the density of states, thermoelectric power, and other properties of these systems could be exploited for enhanced photomechanical actuation, adaptive thin films, or energy harvesting.