Thermoelectric materials capable of converting heat into power and vise versa can be used for a wide range of applications in freon-free refrigerators, waste heat converters, and direct solar thermal energy converters.
A unique class of host-guest compounds, Zintl clathrates exhibit Phonon Glass - Electron Crystal behavior and are considered promising TE materials. This research is supported by DOE BES.
Hydrogen has been proposed to be a clean and carbon-neutral next-generation energy carrier. Compared with curretnyl used steam reforming, water electrolysis represents a cleaner and more sustainable approach to hydrogen generation, but is underdeveloped. To deploy electrolyzers on a large scale and to make the electrolyzed hydrogen fuel economically competitive, it is important to develop nexpensive, earth-abundant electrocatalysts to promote the hydrogen evolution reaction (HER). We are working on transition metal phosphide, silicide, and boride catalysts. This research is supported by NSF CHEM CCAT program.
Binary tetrel-pnicitdes are layered v-d-W materials with exciting properties. Unlike phosphorene and realted materials, silicon- and germanium-pnictides are stable in acidic solutions which open possibilities for flux growth of large crystals using molten metals. Ternary metal tetrel-pnictides exhibit fascinating diversity of sructural motifs and plethora of properties. Polymorphism induced by preferential chemical bonding, ionic conductivity, and non-centrosymmetric semiconductors with second harmonic generation properties are examples of areas we are interested in. This research is supported by DOE BES.
Superconductors are an important type of materials capable of conducting electricity without energy loss and repelling magnetic fields.
Recently discovered Fe-based superconductors are a suitable platform to develop the structure-properties relationship in superconductors. The main structural blocks of Fe-based superconductors are FeX square layers (X = pnictogen or chalcogen). To understand the electronic and magnetic interactions in superconductors, it is preferable to study a single building block. We have developed a low-temperature synthetic route to highly crystalline materials containing Fe-X fragments separated by classical coordination chemistry complexes. This research is supported by NSF DMR SSMC program.