Professional Education


  • Doctor of Philosophy, Seoul National University (2013)
  • Bachelor of Engineering, Seoul National University (2002)

Stanford Advisors


Lab Affiliations


  • Friedrich Prinz, Nanoscale Prototyping Laboratory (9/15/2016 - 9/14/2017)

All Publications


  • Indium-Tin-Oxide Nanowire Array Based CdSe/CdS/TiO2 One-Dimensional Heterojunction Photoelectrode for Enhanced Solar Hydrogen Production ACS SUSTAINABLE CHEMISTRY & ENGINEERING Han, H. S., Han, G. S., Kim, J. S., Kim, D. H., Hong, J. S., Caliskan, S., Jung, H. S., Cho, I. S., Lee, J. 2016; 4 (3): 1161-1168
  • Activating and optimizing MoS2 basal planes for hydrogen evolution through the formation of strained sulphur vacancies (vol 15, pg 48, 2016) NATURE MATERIALS Li, H., Tsai, C., Koh, A. L., Cai, L., Contryman, A. W., Fragapane, A. H., Zhao, J., Han, H. S., Manoharan, H. C., Abild-Pedersen, F., Norskov, J. K., Zheng, X. 2016; 15 (3)

    View details for DOI 10.1038/NMAT4564

    View details for Web of Science ID 000370967400024

  • Enhancing Low-Bias Performance of Hematite Photoanodes for Solar Water Splitting by Simultaneous Reduction of Bulk, Interface, and Surface Recombination Pathways ADVANCED ENERGY MATERIALS Cho, I. S., Han, H. S., Logar, M., Park, J., Zheng, X. 2016; 6 (4)
  • A tree-like nanoporous WO3 photoanode with enhanced charge transport efficiency for photoelectrochemical water oxidation JOURNAL OF MATERIALS CHEMISTRY A Shin, S., Han, H. S., Kim, J. S., Park, I. J., Lee, M. H., Hong, K. S., Cho, I. S. 2015; 3 (24): 12920-12926

    View details for DOI 10.1039/c5ta00823a

    View details for Web of Science ID 000356022800043

  • TiO2 nanocrystals shell layer on highly conducting indium tin oxide nanowire for photovoltaic devices (vol 5, pg 3520, 2013) NANOSCALE Han, H. S., Kim, J. S., Kim, D. H., Han, G. S., Jung, H. S., Noh, J. H., Hong, K. S. 2013; 5 (24): 12674-12674
  • Nanowire-Based Three-Dimensional Transparent Conducting Oxide Electrodes for Extremely Fast Charge Collection ADVANCED ENERGY MATERIALS Noh, J. H., Han, H. S., Lee, S., Kim, J. Y., Hong, K. S., Han, G., Shin, H., Jung, H. S. 2011; 1 (5): 829-835
  • for hydrogen evolution. Nature communications Tsai, C., Li, H., Park, S., Park, J., Han, H. S., Nørskov, J. K., Zheng, X., Abild-Pedersen, F. 2017; 8: 15113-?

    Abstract

    Recently, sulfur (S)-vacancies created on the basal plane of 2H-molybdenum disulfide (MoS2) using argon plasma exposure exhibited higher intrinsic activity for the electrochemical hydrogen evolution reaction than the edge sites and metallic 1T-phase of MoS2 catalysts. However, a more industrially viable alternative to the argon plasma desulfurization process is needed. In this work, we introduce a scalable route towards generating S-vacancies on the MoS2 basal plane using electrochemical desulfurization. Even though sulfur atoms on the basal plane are known to be stable and inert, we find that they can be electrochemically reduced under accessible applied potentials. This can be done on various 2H-MoS2 nanostructures. By changing the applied desulfurization potential, the extent of desulfurization and the resulting activity can be varied. The resulting active sites are stable under extended desulfurization durations and show consistent HER activity.

    View details for DOI 10.1038/ncomms15113

    View details for PubMedID 28429782

  • One-Step Hydrothermal Deposition of Ni:FeOOH onto Photoanodes for Enhanced Water Oxidation ACS ENERGY LETTERS Cai, L., Zhao, J., Li, H., Park, J., Cho, I. S., Han, H. S., Zheng, X. 2016; 1 (3): 624-632
  • CdS-sensitized 1-D single-crystalline anatase TiO2 nanowire arrays for photoelectrochemical hydrogen production 1st International Conference on Nanotechnology, Nanomaterials and Thin Films for Energy Applications (Nano Energy) Kim, D. H., Han, H. S., Cho, I. S., Seong, W. M., Park, I. J., Park, J. H., Shin, S., Do Park, G., Park, S., Lee, S., Hong, K. S. PERGAMON-ELSEVIER SCIENCE LTD. 2015: 863–69
  • Ta-substituted SnNb2-xTaxO6 photocatalysts for hydrogen evolution under visible light irradiation JOURNAL OF MATERIALS CHEMISTRY A Lee, C. W., Park, H. K., Park, S., Han, H. S., Seo, S. W., Song, H. J., Shin, S., Kim, D., Hong, K. S. 2015; 3 (2): 825-831

    View details for DOI 10.1039/c4ta05885b

    View details for Web of Science ID 000346082100046

  • Facile Preparation of TiO2 Nanobranch/Nanoparticle Hybrid Architecture with Enhanced Light Harvesting Properties for Dye-Sensitized Solar Cells JOURNAL OF NANOMATERIALS Kim, J. S., Shin, S. S., Han, H. S., Shin, S., Suk, J. H., Kang, K., Hong, K. S., Cho, I. S. 2015
  • Nanostructured Ti-doped hematite (alpha-Fe2O3) photoanodes for efficient photoelectrochemical water oxidation INTERNATIONAL JOURNAL OF HYDROGEN ENERGY Lee, M. H., Park, J. H., Han, H. S., Song, H. J., Cho, I. S., Noh, J. H., Hong, K. S. 2014; 39 (30): 17501-17507
  • In2O3:Sn/TiO2/CdS heterojunction nanowire array photoanode in photoelectrochemical cells INTERNATIONAL JOURNAL OF HYDROGEN ENERGY Kim, J. S., Han, H. S., Shin, S., Han, G. S., Jung, H. S., Hong, K. S., Noh, J. H. 2014; 39 (30): 17473-17480
  • Heterojunction Fe2O3-SnO2 Nanostructured Photoanode for Efficient Photoelectrochemical Water Splitting JOM Han, H. S., Shin, S., Noh, J. H., Cho, I. S., Hong, K. S. 2014; 66 (4): 664-669
  • A Hierarchically Organized Photoelectrode Architecture for Highly Efficient CdS/CdSe-Sensitized Solar Cells ADVANCED ENERGY MATERIALS Park, J. H., Kim, D. H., Shin, S. S., Han, H. S., Lee, M. H., Jung, H. S., Noh, J. H., Hong, K. S. 2014; 4 (3)
  • Direct Printing Synthesis of Self-Organized Copper Oxide Hollow Spheres on a Substrate Using Copper(II) Complex Ink: Gas Sensing and Photoelectrochemical Properties LANGMUIR Choi, Y., Kim, D., Han, H. S., Shin, S., Hong, S., Hong, K. S. 2014; 30 (3): 700-709

    Abstract

    The direct printing synthesis of metal oxide hollow spheres in the form of film on a substrate is reported for the first time. This method offers facile, scalable, high-throughput production and device fabrication processes. The printing was carried out via a doctor-blade method using Cu(II) complex ink with controllable high viscosity based on formate-amine coupling. Following only thermal heating in air, well-defined polycrystalline copper oxide hollow spheres with a submicrometer diameter (≤1 μm) were formed spontaneously while being assembled in the form of a film with good adhesion on the substrate. This spontaneous hollowing mechanism was found to result from the Kirkendall effect during oxidation at elevated temperature. The CuO films with hollow spheres, prepared via direct printing synthesis at 500 °C, led to the creation of a superior p-type gas sensor and photocathode for photoelectrochemical water splitting with completely hollow cores, a rough/porous shell structure, a single phase, high crystallinity, and no organic/polymer residue. As a result, the CuO hollow-sphere films showed high gas responses and permissible response speeds to reducing gases and high photocurrent density compared to conventional CuO powder films and the values previously reported. These results exemplify the successful realization of a high-throughput printing fabrication method for the creation of superior nanostructured devices.

    View details for DOI 10.1021/la404098s

    View details for Web of Science ID 000330543700004

    View details for PubMedID 24422661

  • 1-D Structured Flexible Supercapacitor Electrodes with Prominent Electronic/Ionic Transport Capabilities ACS APPLIED MATERIALS & INTERFACES Kim, J. S., Shin, S. S., Han, H. S., Oh, L. S., Kim, D. H., Kim, J., Hong, K. S., Kim, J. Y. 2014; 6 (1): 268-274

    Abstract

    A highly efficient 1-D flexible supercapacitor with a stainless steel mesh (SSM) substrate is demonstrated. Indium tin oxide (ITO) nanowires are prepared on the surface of the stainless steel fiber (SSF), and MnO2 shell layers are coated onto the ITO/SSM electrode by means of electrodeposition. The ITO NWs, which grow radially on the SSF, are single-crystalline and conductive enough for use as a current collector for MnO2-based supercapacitors. A flake-shaped, nanoporous, and uniform MnO2 shell layer with a thickness of ~130 nm and an average crystallite size of ~2 nm is obtained by electrodeposition at a constant voltage. The effect of the electrode geometry on the supercapacitor properties was investigated using electrochemical impedance spectroscopy, cyclic voltammetry, and a galvanostatic charge/discharge study. The electrodes with ITO NWs exhibit higher specific capacitance levels and good rate capability owing to the superior electronic/ionic transport capabilities resulting from the open pore structure. Moreover, the use of a porous mesh substrate (SSM) increases the specific capacitance to 667 F g(-1) at 5 mV s(-1). In addition, the electrode with ITO NWs and the SSM shows very stable cycle performance (no decrease in the specific capacitance after 5000 cycles).

    View details for DOI 10.1021/am404132j

    View details for Web of Science ID 000329586300037

    View details for PubMedID 24397749

  • Surface-area-tuned, quantum-dot-sensitized heterostructured nanoarchitectures for highly efficient photoelectrodes NANO RESEARCH Park, S., Kim, D., Lee, C. W., Seo, S., Kim, H. J., Han, H. S., Hong, K. S., Kim, D. 2014; 7 (1): 144-153
  • Aligned Photoelectrodes with Large Surface Area Prepared by Pulsed Laser Deposition JOURNAL OF PHYSICAL CHEMISTRY C Noh, J. H., Park, J. H., Han, H. S., Kim, D. H., Han, B. S., Lee, S., Kim, J. Y., Jung, H. S., Hong, K. S. 2012; 116 (14): 8102-8110

    View details for DOI 10.1021/jp211233s

    View details for Web of Science ID 000302591300063

  • Facile hydrothermal synthesis of InVO4 microspheres and their visible-light photocatalytic activities MATERIALS LETTERS Noh, T. H., Kim, D. W., Seo, S. W., Cho, I. S., Kim, D. H., Han, H. S., Hong, K. S. 2012; 72: 98-100
  • Tin doped indium oxide core-TiO2 shell nanowires on stainless steel mesh for flexible photoelectrochemical cells APPLIED PHYSICS LETTERS Noh, J. H., Ding, B., Han, H. S., Kim, J. S., Park, J. H., Park, S. B., Jung, H. S., Lee, J., Hong, K. S. 2012; 100 (8)

    View details for DOI 10.1063/1.3684805

    View details for Web of Science ID 000300711200074

  • A Newly Designed Nb-Doped TiO2/Al-Doped ZnO Transparent Conducting Oxide Multi layer for Electrochemical Photoenergy Conversion Devices JOURNAL OF PHYSICAL CHEMISTRY C Noh, J. H., Han, H. S., Lee, S., Kim, D. H., Park, J. H., Park, S., Kim, J. Y., Jung, H. S., Hong, K. S. 2010; 114 (32): 13867-13871

    View details for DOI 10.1021/jp104247t

    View details for Web of Science ID 000280727500064

  • Tailoring the Morphology and Structure of Nanosized Zn2SiO4: Mn2+ Phosphors Using the Hydrothermal Method and Their Luminescence Properties JOURNAL OF PHYSICAL CHEMISTRY C An, J., Noh, J. H., Cho, I., Roh, H., Kim, J. Y., Han, H. S., Hong, K. S. 2010; 114 (23): 10330-10335

    View details for DOI 10.1021/jp911731s

    View details for Web of Science ID 000278479700002

  • Enhancing the Densification of Nanocrystalline TiO2 by Reduction in Spark Plasma Sintering JOURNAL OF THE AMERICAN CERAMIC SOCIETY Noh, J. H., Jung, H. S., Cho, I., An, J., Cho, C. M., Han, H. S., Hong, K. S. 2010; 93 (4): 993-997
  • Photoluminescence and electrical properties of epitaxial Al-doped ZnO transparent conducting thin films PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE Noh, J. H., Cho, I., Lee, S., Cho, C. M., Han, H. S., An, J., Kwak, C. H., Kim, J. Y., Jung, H. S., Lee, J., Hong, K. S. 2009; 206 (9): 2133-2138
  • Nb-Doped TiO2: A New Compact Layer Material for TiO2 Dye-Sensitized Solar Cells JOURNAL OF PHYSICAL CHEMISTRY C Lee, S., Noh, J. H., Han, H. S., Yim, D. K., Kim, D. H., Lee, J., Kim, J. Y., Jung, H. S., Hong, K. S. 2009; 113 (16): 6878-6882

    View details for DOI 10.1021/jp9002017

    View details for Web of Science ID 000265383300074

  • Functional Multilayered Transparent Conducting Oxide Thin Films for Photovoltaic Devices JOURNAL OF PHYSICAL CHEMISTRY C Noh, J. H., Lee, S., Kim, J. Y., Lee, J., Han, H. S., Cho, C. M., Cho, I. S., Jung, H. S., Hong, K. S. 2009; 113 (3): 1083-1087

    View details for DOI 10.1021/jp808279j

    View details for Web of Science ID 000262522000040