ChBE Seminar Series - Hyunjoo Lee

Wed Sep 18 3:00 pm to 4:00 pm
MoSE "M" Building, Room G011

Unless otherwise noted, all Seminar Series events are held at 3 p.m. in the MoSE "M" Building (Room G011). Refreshments are served in advance starting at 2:30 p.m. outside of GO11.

Dr. Hyunjoo Lee - Department of Chemical and Biomolecular Engineering, Korea Advanced Inst. of Science and Technology

“Design and Applications of Supported Metal Nanoparticle Catalysts”

Abstract:

Heterogeneous catalysts have been widely used to produce energy or chemicals. We have controlled the shape/composition of the supported nanoparticle catalysts or the interaction between metal active phase and support in order to enhance activity, selectivity, and durability. For applications, we have worked on automobile exhaust treatment, direct methane oxidation, plasmonic reactions, proton exchange membrane fuel cells (PEMFC), water electrolyzers, etc. Recently, we have synthesized precious metal (Pt, Rh, Pd) single-atom catalysts or ensemble catalysts by maximizing the interaction between precious metal and supports. The single-atom catalysts (SAC) showed unique selectivity distinct from nanoparticle catalysts, and its activity could be enhanced by an order of magnitude. Rh SAC immobilized on ZrO2 could catalyze direct methane oxidation to methanol or ethane. One of our Pt electro-SACs showed remarkable activity and durability; its single atomic structure could be retained even after repeating cyclic voltammetry in 0.05-1.4 V, where the conventional Pt/C catalyst would be completely destroyed. We also succeeded preparing a full cell using the Pt SACs; we used only 1/10 of Pt to produce the same electricity. More recently, we reported Rh ensemble catalyst with 100% dispersion yet with ensemble sites. The ensemble catalysts showed exceptionally high mass activity and durability for diesel oxidation or three way conversion reactions. Rational design of supported nanoparticle catalyst can contribute to producing energy and chemical in more efficient and environmentally more sustainable way.

Bio:

Prof. Hyunjoo Lee received her B.S. and M.S. degrees from Seoul National University (South Korea) and Ph.D. from California Institute of Technology (USA). She performed her post-doctoral research in University of California, Berkeley (USA). Since 2014, she has worked in Korea Advanced Institute of Science and Technology (KAIST). Her research focuses on the control of nanostructures in heterogeneous catalysts. She has developed various shape/composition-controlled nanoparticle catalysts or precious metal single-atom catalysts, and used them for gas-phase reactions (methane direct oxidation, automobile exhaust treatment, hydrocarbon reforming reaction) and electrochemical reactions (PEMFC, water electrolyzers, CO2 reduction). (http://catmat.kaist.ac.kr)

 

Location

MoSE "M" Building, Room G011