Understanding thermal transport at the nano and mesoscale is crucial to designing efficient thermoelectric devices. Our group focuses on designing novel thermoelectric architectures and understanding their thermal ane electronic behavior at various scales using a combination of atomistic and continuum scale calculations. Currently, we are designing functionalized forms of graphene and nanoporous silicon that exhibit low thermal conductivity, and at the same time show high electronic conductivity – a useful characteristic for applications in thermoelectric devices.
Solar Thermal Fuels
Photocontrolled self-assembly and disassembly of solar thermal fuels (STFs) based on diacetylene derivatives with azobenzene moieties are investigated and found to significantly increase the energy storage density in the STFs. The azobenzene-decorated diacetylenes and polydiacetylenes are high energy-density materials that can store more than double the density of pristine azobenzene. The extra energy storage in the materials in addition to the isomerization enthalpy of azobenzene units is enabled by the different phase of materials in the ground state (crystalline solid) and in metastable state (amorphous solid/liquid).
[1] G. D. Han, S. S. Park, Y. Liu, D. Zhitomirsky, E. Cho, M. Dincă, J. C. Grossman, Photon energy storage materials with high energy densities based on diacetylene–azobenzene derivatives. J. Mater. Chem. A (2016) Advanced Article, DOI: 10.1039/C6TA07086H