Developing the energy technologies of the future will rely heavily on advances in materials — whether it be safe reliable nuclear reactors, next-gen solar cells, or thermoelectric devices for waste heat recovery. Understanding how to control the flow of energy carried by the motion of atoms in materials (phonons, molecular modes, etc.) is often crucial. In this talk, I will present two examples, one on a photovoltaic (solar) material, and the other on a thermoelectric material.

We use neutron scattering and other techniques to show that thermal transport can be reduced by swapping out a lighter isotope for a heavier one in the organic molecule of the high-performance photovoltaic material methylammonium lead iodide. For thermoelectric efficiency an ideal is the phonon glass–electron crystal. This drives research on strategies to scatter or localize phonons while minimally disrupting electrons. These examples highlight how observing the motions of atoms can bare new strategies for enhancing the performance of energy materials.

ZOOM LINK

Meeting ID: 960 4405 0376
Passcode: 107155