1

Dr. Kwangjin An

Kwangjin An received his BS (2003) in the  School of Chemical Engineering from Chungnam National University and his PhD (2009) in the School of Chemical and Biological Engineering from Seoul National University. During his PhD course under the direction of professor Taeghwan Hyeon, he had conducted research on the synthesis and characterization of monodisperse metal-oxide nanocrystals. Since he joined UC Berkeley, his research interests have been focused surface science and catalysis using nanoparticle-based catalysts.

Professional Experience

  • 2019.82015.5

    Associate Professor

    UNIST, School of Energy and Chemical Engineering

  • 2015.42010.9

    Postdoctoral Research Fellow

    Department of Chemistry, University of California at Berkeley (Advisor: Prof. Gabor A. Somorjai)

  • 2010.82009.2

    Postdoctoral Research Fellow

    Institute of Chemical Process, Seoul National University (Advisor: Prof. Taeghwan Hyeon)

Education

  • Ph.D. 2009.2

    M.S & Ph.D. in Chemical and Biological Engineering

    Seoul National University (Advisor: Prof. Taeghwan Hyeon)

  • B.A. 2003.2

    Bachelor in Chemical Engineering (Fine Chemical Engineering Major)

    Chungnam National University

Research

2
  • Development of Functional Nanostructured Catalysts

    Development of Functional Nanostructured Catalysts

    Novel synthesis of metallic, bimetallic, and core@shell nanoparticles with well-defined structures to design the best catalysts with high activity and selectivity in catalytic reactions.

    Industrial heterogeneous catalysts, composed of metal nanoparticles, have been widely utilized owing to their high surface to volume ratio. However, the broad size distribution of these particles, and the lack of structural characterization have been obstacles in understanding their structure-dependent catalytic activity and selectivity.

    A nanoparticle with well-defined surfaces, prepared through colloidal chemistry, enables it to be studied as a model heterogeneous catalyst.

    In the present laboratory, we develop nanoparticle catalysts with controlled morphologies which provide more active sites to lower activation energy for catalytic reactions, and unique surface structures—such as steps, kinks, and terraces—to influence reaction pathways leading to product selectivity.

    As catalytic behaviors can also be altered at oxide-metal interfaces, porous support materials with high surfaces and ordered pore structures will be desinged as well in this lab.

  • Understanding of the mechanisms of important catalytic reactions

    Understanding of the mechanisms of important catalytic reactions

    Rational design of catalysts, by understanding reaction kinetics and finding transition-paths

    Achieving the highest performance in catalytic reaction is an essential goal of the chemical industry.

    In aiming to develop catalysts with the highest product yields and process stability, we concentrate our effort on understanding at the molecular level how the active component’s particle size and shape, elemental composition, interaction with the support, presence of a surface dopant, catalytic poison, or capping agent affect the catalytic performance in industrially significant reactions.

     

    → On-going Catalytic Reactions

    1. CO Oxidation and Hydroformylation over Nanoparticle Arrays: Monodisperse Pt, Pd, and Au NPs on CeO2 or TiO2 NPs  (Binary Nanoparticle Superlattices) are used as 2-D Film Catalysts in Gas-phase Batch Reactor
    2. Methane Partal Oxidation over Supported V2O5 Catalysts: Importantant Catalytic Reaction by Converting Abundent C1 Molecules to Valuable Chemicals in Gas-phase Flow Reactor.
    3. Furfural Hydrogenation As a Biomass Conversion: Pd NPs on Activated Carbon Materials in Liquid-phase Batch Reactor.
  • Finding molecular factors affecting catalytic activity and selectivity using in situ characterization tools to understand surface phenomena.

    Finding molecular factors affecting catalytic activity and selectivity using in situ characterization tools to understand surface phenomena.

    Application of spectroscopic and microscopic methods with high spatial and energy resolution to establish useful structure-function relationships under catalytic reaction conditions.

    Based on current model reaction studies, it has been proven that turnover rates and selectivity of reactions were strongly influenced by the size, shape, and composition of nanoparticles and strong oxide-metal interactions, which are created by various metal-oxide interfaces.

    With the evolution of in situ characterization techniques, we discovered that several molecular factors influenced catalytic activity and selectivity including surface structure and composition of nanoparticles, reaction intermediates, adsorbates, and oxidation states in nanocatalysis.

     

    Especially, the interaction between the active metal and the oxide support induces charge transfer, resulting in enhancement of catalytic reaction rates and changing product selectivity.

    These phenomena are called as the strong metal-support interaction (SMSI). Recent studies have demonstrated that electronic excitation in exothermic reactions involves the hot electron flow at oxide-metal interfaces.

    When we utilize SMSI, catalytic performance can be improved beyond the intrincsic properties of metal or support. By maximizing the interfacial effect, we can develop new catalysts and catalytic systems, having outstanding performance with minmum consumption of novel metals.

  • Extend the knowledge getting from catalysis for development of new industrial catalysts.

    Extend the knowledge getting from catalysis for development of new industrial catalysts.

    Advances in nanoscience and technology provide opportunities for developing next-generation energy systems with novel catalysts with high activities for energetically challenging reactions, high selectivity to valuable products, and extended life times.

    We will focus on technology transfer and commercialization with newly developed nanocatalysts.