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Google scholar profile_https://scholar.google.com/citations?authuser=1&user=MMIaMDkAAAAJ
Linked in profile_https://www.linkedin.com/in/%E2%80%8Dsang-won-lee-918495226/

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All Publications


  • Homogeneously Mixed Cu-Co Bimetallic Catalyst Derived from Hydroxy Double Salt for Industrial-Level High-Rate Nitrate-to-Ammonia Electrosynthesis. Journal of the American Chemical Society Jang, W., Oh, D., Lee, J., Kim, J., Matthews, J. E., Kim, H., Lee, S. W., Lee, S., Xu, Y., Yu, J. M., Hwang, S. W., Jaramillo, T. F., Jang, J. W., Cho, S. 2024

    Abstract

    Electrocatalytic nitrate reduction reaction (NO3RR) presents an innovative approach for sustainable NH3 production. However, selective NH3 production is hindered by the multiple intermediates involved in the NO3RR process and the competitive hydrogen evolution reaction. Hence, the development of highly efficient NO3RR catalysts is paramount. Herein, we report highly efficient bimetallic catalysts derived from hydroxy double salt (HDS). Under NO3RR conditions, Cu1Co1-HDS undergoes in situ reconstruction, forming nanocomposites of homogeneously distributed metallic Cu0 and Co(OH)2. Reconstruction-induced Cu0 rapidly converts NO3- to NO2-, which is further hydrogenated to NH3 by Co(OH)2. Homogeneously mixed Cu and Co species maximize this synergistic effect, achieving outstanding NO3RR performance including the highest NH3 yield rate (4.625 mmol h-1 cm-2) reported for powder-type NO3RR catalysts. Integration of Cu1Co1-HDS with a commercial Si solar cell attained 4.53% solar-to-ammonia efficiency from industrial wastewater-level concentrations of NO3- (2000 ppm), demonstrating practical application potential for solar-driven NH3 production. This study provides a strategy for enhancing the NH3 yield rate by optimizing the compositions and distributions of Cu and Co.

    View details for DOI 10.1021/jacs.4c07061

    View details for PubMedID 39177778

  • CO<sub>2</sub> Conversion to Butene via a Tandem Photovoltaic-Electrochemical/Photothermocatalytic Process: A Co-design Approach to Coupled Microenvironments ACS ENERGY LETTERS Yap, K. K., Aitbekova, A., Salazar, M., Kistler, T. A., Pabon, M., Su, M. P., Watkins, N. B., Lee, S., Agbo, P., Weber, A. Z., Peters, J. C., Agapie, T., Nielander, A. C., Atwater, H. A., Jaramillo, T. F., Bell, A. T. 2024
  • Sub-volt conversion of activated biochar and water for H2 2 production near equilibrium via biochar-assisted water electrolysis CELL REPORTS PHYSICAL SCIENCE Kani, N. C., Chauhan, R., Olusegun, S. A., Sharan, I., Katiyar, A., House, D. W., Lee, S., Jairamsingh, A., Bhawnani, R. R., Choi, D., Nielander, A. C., Jaramillo, T. F., Lee, H., Oroskar, A., Srivastava, V. C., Sinha, S., Gauthier, J. A., Singh, M. R. 2024; 5 (6)
  • Titanium Silicide: A Promising Candidate of Recombination Layer for Perovskite/Tunnel Oxide Passivated Contact Silicon Two-Terminal Tandem Solar Cells. ACS applied materials & interfaces Pyun, D., Choi, D., Bae, S., Lee, S. W., Song, H., Jeong, S. H., Lee, S., Hwang, J. K., Cho, S., Lee, H., Woo, M., Lee, Y., Kim, K., Kim, Y., Lee, C., Choe, Y., Kang, Y., Kim, D., Lee, H. S. 2024

    Abstract

    This study proposes a titanium silicide (TiSi2) recombination layer for perovskite/tunnel oxide passivated contact (TOPCon) 2-T tandem solar cells as an alternative to conventional transparent conductive oxide (TCO)-based recombination layers. TiSi2 was formed while TiO2 was made by oxidizing a Ti film deposited on the p+-Si layer. The reaction formation mechanism was proposed based on the diffusion theory supported by experimental results. The optical and electrical properties of the TiSi2 layer were optimized by controlling the initial Ti thicknesses (5-100 nm). With the initial Ti of 50 nm, the lowest reflectance and highly ohmic contact between the TiO2 and p+-Si layers with a contact resistivity of 161.48 mΩ·cm2 were obtained. In contrast, the TCO interlayer shows Schottky behavior with much higher contact resistivities. As the recombination layer of TiSi2 and the electron transport layer of TiO2 are formed simultaneously, the process steps become simpler. Finally, the MAPbI3/TOPCon tandem device yielded an efficiency of 16.23%, marking the first reported efficiency for a device including a silicide-based interlayer.

    View details for DOI 10.1021/acsami.4c01864

    View details for PubMedID 38771721

  • Maximizing efficiency: Numerical modeling and optimization of 2-terminal perovskite/silicon tandem devices with different bottom cell structures SOLAR ENERGY Song, H., Lee, S., Kang, Y., Kim, D., Lee, H. 2024; 273
  • Bias-free solar NH<sub>3</sub> production by perovskite-based photocathode coupled to valorization of glycerol NATURE CATALYSIS Tayyebi, A., Mehrotra, R., Al Mubarok, M., Kim, J., Zafari, M., Tayebi, M., Oh, D., Lee, S., Matthews, J. E., Lee, S., Shin, T., Lee, G., Jaramillo, T. F., Jang, S., Jang, J. 2024
  • Modeling diurnal and annual ethylene generation from solar-driven electrochemical CO<sub>2</sub> reduction devices ENERGY & ENVIRONMENTAL SCIENCE Yap, K. K., Wei, W. J., Pabon, M., King, A. J., Bui, J. C., Wei, L., Lee, S., Weber, A. Z., Bell, A. T., Nielander, A. C., Jaramillo, T. F. 2024

    View details for DOI 10.1039/d4ee00545g

    View details for Web of Science ID 001176280900001

  • Controlling Mass Transport in Direct Carbon Dioxide Zero-Gap Electrolyzers via Cell Compression ACS SUSTAINABLE CHEMISTRY & ENGINEERING Lee, D., Joensen, B., Jenny, J., Ehlinger, V. M., Lee, S., Abiose, K., Xu, Y., Sarkar, A., Lin, T. Y., Hahn, C., Jaramillo, T. F. 2023; 11 (46): 16661-16668
  • Potassium chloride passivation for sputtered SnO2 to eliminate hysteresis and enhance the efficiency of perovskite solar cells JOURNAL OF ALLOYS AND COMPOUNDS Jeong, S., Hwang, J., Hwang, J., Lee, S., Lee, W., Lee, S., Pyun, D., Cho, S., Choe, Y., Lee, H., Kim, D., Kang, Y. 2023; 968
  • A framework for understanding efficient diurnal CO2 reduction using Si and GaAs photocathodes CHEM CATALYSIS Yap, K. K., Lee, S., Steiner, M. A., Acosta, J., Kang, D., Kim, D., Warren, E. L., Nielander, A. C., Jaramillo, T. F. 2023; 3 (6)
  • Sputtered PbI2 with Post-Processing for Perovskite Solar Cells SOLAR RRL Hwang, J., Lee, S., Lee, W., Bae, S., Kang, D., Jeong, S., Lee, S., Pyun, D., Hwang, J., Cho, S., Kim, D., Kang, Y., Lee, H. 2023
  • First Demonstration of Top Contact-Free Perovskite/Silicon Two-Terminal Tandem Solar Cells for Overcoming the Current Density Hurdle ACS APPLIED ENERGY MATERIALS Pyun, D., Lee, S., Kim, Y., Jang, G., Choi, D., Jeong, S., Song, H., Lee, S., Cho, S., Kim, J., Kang, D., Lee, H., Hyun, J., Lee, C., Park, H., Hwang, J., Lee, W., Jeon, N., Seo, J., Kang, Y., Kim, D., Lee, H. 2023