(6af) Nanostructured Transition Metal Dichalcogenide Catalysts for Electrochemical Energy Systems

Mohammad Asadi

Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.

Abstract:

Electrochemical energy systems have shown a tremendous potential to store energy in the form of chemical bonds using renewable energy sources. In general, energy can be converted or stored into chemical bonds through catalytic electrochemical processes such as fuel cells, oxygen reduction reaction (ORR) and carbon dioxide reduction reaction (CO₂RR). However, in practice existing catalysts are too inefficient: either weak binding interactions between the reaction intermediates and the catalyst give rise to high overpotentials, or slow electron transfer kinetics result in low exchange current densities. Both of these metrics depend not only on the intrinsic electronic properties of the catalyst, but also on the solvent and the catalyst morphology.

Here, I present the nanoarchitectures two-dimensional (2D) of molybdenum disulfide (MoS₂) and other transition metal dichalcogenides (TMDs) that manifest much higher performance for electrocatalytic ORR and CO₂RR reactions in the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF₄). Atomic level study of TMD nanoflakes before and after electrochemical experiments using scanning transmission electron microscopy (STEM) indicate that; (i) mainly metallic edge atoms are responsible for this remarkable activity and (ii) the edge atoms remain stable during the reactions. Moreover, I have successfully tested MoS₂ nanoflakes that work with the ionic liquid EMIM-BF₄ electrolyte as an effective co-catalyst for discharge and charge in a Li-O₂ battery.

The presented TMDs/IL co-catalyst system with remarkable electrocatalytic performance could open a new route to the advancement of energy conversion and storage systems.

Research Interests:

1- Synthesis and characterization of catalysts

2- Energy conversion systems (i.e., CO₂reduction reaction, water splitting, hydrogen evolution reaction, oxygen reduction reaction, oxygen evolution reaction)

3- Energy storage systems (i.e., metal-ion and metal-air batteries)

4- Electrochemisty and photoelectrochemistry

Teaching Interests:

1- Fluid Mechanics

2- Thermodynamics

3- Heat Transfer

4- Transport Phenomena

5- Reaction Engineering

6- Mass Transfer

store energy in into the chemical bonds in the form of electricity or fuel.