(4cu) Surface/Interfacial Engineering for Energy Conversion (SEEC)

The surface/interfacial properties have strong effects on the chemical and physical properties of materials. With the unique background and expertise in surface chemistry, materials engineering on atomic/molecular scales, surface chemical and physical properties characterization, electrochemical/photoelectrochemical analysis, catalysis, and chemical engineering, I am well prepared for doing cutting-edge research in advancing the fundamental understanding of surface/interfacial mechanisms in materials engineering for renewable photoelectrochemical H₂ production and catalytic conversion of fuels. My particular research interests are centered in the following related fields.  

I.    Hydrogen Production from Photoelectrolysis of Water

Photoelectrochemical (PEC) water splitting for H₂ production is a sustainable mean to clean energy. However, current photoelectrode materials either suffer from low solar-to-H₂ (STH) efficiency or decomposition. Two topics will be studied. In Topic I-1, I will focus on using atomic layer deposited metal oxide coatings to improve the corrosion resistance of photoelectrode materials of high efficiency, such as GaAs and InP. The protective metal oxide layer must be pinhole free and well-bonded, allow facile charge transfer, and have low density of interfacial defects, which pose a great challenge for materials engineering. The research will gain understanding of the effect atomic layer deposition (ALD) coatings on the corrosion resistance and efficiency of the oxide coated photoelectrodes.  Topic I-2 is devoted to develop high efficient Fe₂O₃ PEC photoelectrodes. In this project, I will study heterogeneous nucleation and growth of Fe₂O₃ nanorods through a sequential pulsing vapor deposition process. The effects of supporting scaffold, interface between materials, doping, and Fe₂O₃ nanorod morphology and surface property on STH efficiency of Fe₂O₃ photoelectrodes will be investigated systematically to improve the understanding of the mechanisms underlying Fe₂O₃ photoelectrodes and to further improve the STH efficiency of Fe₂O₃photoelectrodes through rational design.

II.  Advanced Catalysts Design, Synthesis and Characterization

Catalysts are important for all chemical processes. Synthesizing designer catalysts with atomic precision is the key to understand and improve the catalytic properties of materials. Two topics will be investigated. Topic II-1 involves designing and engineering advanced colloid catalysts with ALD and molecular layer deposition (MLD). The well-defined particle size and crystal facet of colloid particles are highly desired for fundamental studies and practical catalytic reactions. However, the stabilizing ligands often existed on the surface of colloid particles are detrimental for their catalytic properties. I will investigate the synergetic effect of surface capping ligands and ALD/MLD chemistries on the catalytic properties of colloid particles. Topic II-2 spotlights on synthesis of model complex multiple components layered metal/oxides/sulfide/nitride tandem catalysts. The study aims to explore and understand the cooperative catalytic effects from the nanoscale adjacent catalytic domains on a single catalyst body. Emphasis will be put on fundamental understanding of the surface and interfacial mechanisms during the assembly of different components and their effects on the catalytic properties of final tandem catalysts.