Miller Associate Professor, 2014-present, University of Kansas
Assistant Professor, 2010-2014, University of Notre Dame
Postdoctoral Fellow, 2006-2010, University of California at Berkeley and Lawrence Berkeley National Lab
PhD, 2002-2006, Princeton University
National Science Foundation Career Award, 2014-2019
Fellow, Royal Society of Chemistry, 2013
Paul Holloway Award, American Vacuum Society, 2012
Gerhard Ertl (Nobel Laureate 2007) Young Investigator Award (Finalist Prize), 2010
Eugene P. Wigner (Nobel Laureate 1963) Fellowship, ORNL, 2010
IUPAC Prize for Young Chemists (Dissertation), 2008
Heterogeneous catalysis is crucial for chemical and energy transformation. Our research focuses on the interdisciplinary field of heterogeneous catalysis, nanoscience, materials chemistry, and surface science. We are interested in important catalytic reactions of chemical and energy transformations. The goals of our research projects are to achieve fundamental understanding of important catalytic reactions at molecular level and develop efficient nanocomposite catalytic systems through integration of synthesis, evaluation of catalytic performance, and in-situ and operando characterizations.
We perform in-situ/operando characterization with our laboratory-based ambient pressure photoelectron spectrometer and ambient pressure high temperature scanning tunneling microscope in our group. These studies provide in-situ information of nanocatalysts under a reaction condition or during catalysis.
Our Specific Projects
- Synthesis and catalysis of shape-controlled early transition metal oxide and mixed transition metal oxide
In this project, transition metal oxide and mixed oxide are synthesized. Fundamental studies of catalysis in them are performed. For example, Co3O4 nanorods were synthesized. CoO nanorods formed from Co3O4 exits high selective and activity for reduction of NO with CO at relatively low reaction temperature. Mixed oxides such as Co3-xNixO4 were synthesized. They are highly active for complete oxidation of methane.
- Preparation and catalysis of singly dispersed metal atoms on oxide (single atom catalyst)
In this project, precious metal atoms such as Pt atoms are anchored on surface of oxide such as Co3O4. They exhibit low activation barrier for reactions including water gas shift.
- Synthesis and catalysis of singly dispersed bimetallic site catalyst
In this project, bimetallic sites were prepared through a controlled oxidation and reduction. These sites are singly dispersed on an oxide support. The cationic state of bimetallic sites in these catalysts offers different catalytic performances in contrast to bimetallic sites of a bimetallic nanoparticle.
- Catalysis and in-situ studies of shape-controlled bimetallic nanoparticle catalyst
In this project, bimetallic nanoparticles with well controlled shape such as Rh-Pd nanocubes are used as catalysts for evaluation of catalytic performances and in-situ characterization. Correlation between surface structure and catalytic performance is built.
- Restructuring surface structure of nanoparticle catalyst toward achieving better catalytic performance
In this project, a gas phase reaction on a bimetallic nanoparticle is performed to restructure the surface to tune its catalytic performance. One example is the restructured Pt-Cu nanocubes exhibit much high catalytic activity for CO oxidation than as-synthesized one.
- Development of new catalysts for intermediate temperature solid oxide fuel cell technology
In this project, catalysts with high activity in reforming methane at an intermediate temperature are prepared for intermediate temperature solid oxide fuel cell process.
- Synthesis and in-situ studies of mesoporous metal catalysts
In this project, Fe-based mesoporous metal catalysts are being developed for important chemical transformations including selective oxidation and hydrogenation. Fundamental understanding of catalysis in this type of materials will be achieved through in-situ studies.
- Methane conversion on zeolite anchored with transition metal atoms
In this project, zeolites such as ZSM5 is used to anchor atoms of a transition metal for catalytic conversion of CH4 to methanol and other oxygenates in a liquid phase.
- Structural evolution of nanoparticle catalysts under reaction conditions or during catalysis
In this project, structural evolution of metal and oxide nanocatalysts in gas phase of reactant is tracked with in-situ characterization techniques including ambient pressure XPS, ambient pressure STM, environmental TEM, and in-situ EXAFS.
- Fundamental studies of surface structure and chemistry of metal and oxide model catalysts in gas phase or during catalysis
In this project, surface structure and chemistry of model catalysts including Rh(110) and Co3O4 thin film are studied with AP-STM and AP-XPS toward building a correlation between surface structure/chemistry and the corresponding catalytic performance for a fundamental understanding of prototype catalytic reactions.
- Fundamental understanding of surface of photocatalyst and its cocatalysts
In this project, surface of a photocatalysts and cocatalysts of photocatalytic system active for water spitting is studied by using in-situ surface analytic techniques with a goal of understanding the photocatalytic process from surface science point of view.
- Instrumentation for tracking surface of metal or oxide at solid-gas and solid-liquid interfaces
In this project, instrumentation toward tracking surface structure and chemistry of nanocatalysts buried in a gas phase with higher pressure or liquid phase of a reactant is being developed.