Thursday, April 4, 2024 - 3:30pm

Abstract: 1D or 2D metal chalcogenide exhibit a plethora of interesting properties ranging from magnetism and superconductivity to catalysis. We developed a unique set of hybrid compounds composed of infinite 1D or 2D iron-chalcogenide fragments and 0D coordination complexes. In this way the magnetic interactions and tunability can be segregated into two different sublattices of a hybrid material. Utilizing coordination chemistry methodology to tune the molecular amine complexes we can manipulate the composition structure and properties of the hybrid materials. Selected examples include inducing of ferro or ferrimagnetic exchange in 1D chains, inducing chirality via inorganic linkers, and realization of the mix-valent compounds. Synthetic explorations resulted in the development of novel method of Se activation allowing to produce a diverse set of inorganic chalcogenides. The developed activated Se precursor allows us to produce Ag2Se-based materials via benchtop room temperature chemistry. The developed synthetic method opens ways for precise doping of Ag2Se allowing to regulate transport properties. We demonstrated Ag2Se-based materials with remarkable thermoelectric performance with a maximum zT of 1.3 and averaged zT of 1.15 in 25-120°C range which outperforms all reported Ag2Se materials and is on par with the best n-type Bi2Te3 and Mg3Bi2 materials. The latter materials require high-temperatures and complex synthetic modifications, while our synthesis employs a simple and sustainable benchtop chemistry to yield efficient room temperature thermoelectrics.


Kirill Kovnir


Iowa State University


RH 104