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Papers for 2024~Present


We pursue valuable research and continuously publish papers. Through these publications, both large and small

we solve problems and contribute to the preservation of people, the environment, and the planet. 

  Nature Communications

    April 2024  vol 15 : No1. 3356 


“Extrinsic hydrophobicity-controlled silver nanoparticles

  as efficient and stable catalysts for CO₂ electrolysis”


    Young-Jin Ko, Chulwan Lim, Junyoung Jin, Min Gyu Kim, Ji Yeong Lee, Tae-Yeon Seong,

    Kwan-Young Lee, Byoung Koun Min, Jae-Young Choi, Taegeun Noh, Gyu Weon Hwang,

    Woong Hee Lee, Hyung-Suk Oh.

     Abstract

     To realize economically feasible electrochemical CO₂ conversion, achieving a high partial current density for

      value-added products is particularly vital. However, acceleration of the hydrogen evolution reaction

      due to cathode flooding in a high-current-density region makes this challenging. Herein, we find that partially

      ligand-derived Ag nanoparticles (Ag-NPs) could prevent electrolyte flooding while maintaining catalytic activity

      for CO₂ electroreduction. This results in a high Faradaic efficiency for CO (>90%) and high partial current density        (298.39 mA cm‒2), even under harsh stability test conditions (3.4 V). The suppressed splitting/detachment of Ag

      particles... ...

  Advanced Energy Materials

  January 2024  vol 14 : 2302971 (co-first author)


“Activity Restoration of Pt–NiOctahedron via Phase

  Recovery for Anion Exchange Membrane‐Unitized

  Regenerative Fuel Cells”



   Young-Jin Ko, Chulwan Lim, Junyoung Jin, Min Gyu Kim, Ji Yeong Lee, Tae-Yeon Seong,

   Kwan-Young Lee, Byoung Koun Min, Jae-Young Choi, Taegeun Noh, Gyu Weon Hwang,

   Woong Hee Lee, Hyung-Suk Oh.

   Abstract
    Unitized regenerative fuel cells (URFCs) offer a cost-effective solution for energy conversion by functioning as
     both fuel cells and electrolyzers. Anion-exchange membrane-based URFCs (AEM-URFCs) require bifunctional
     electrocatalysts, such as Pt–Ir alloys, for the oxygen evolution reaction (water electrolysis mode) and oxygen
     reduction reaction (fuel cell mode). However, the low stability of Pt in alkaline media and the high cost... ...

  ACS Energy Letters

    April 2024  vol 9 : Issue 7


“Deriving an Efficient and Stable Microenvironment

  for a CO₂ MEA Electrolyzer by Reverse Osmosis”


  Jaeyong Park, Eung-Dab Kim, Sangkuk Kim, Chulwan Lim, Hyunchul Kim, Young-Jin Ko,

  Jae-Young Choi, Hyung-Suk Oh, Woong Hee Lee.

 Abstract

 In a membrane electrode assembly (MEA) electrolyzer based on a cation-exchange membrane, achieving an
 efficient and stable CO₂ reduction reaction (CO₂RR) is challenging because the transport of protons, cations,

 and electro-osmotic water from the anode changes the balance of ions. Herein, we derived a microenvironment for   stable and efficient CO₂RR performance by using two strategies. First, a mixture of carbon and anion-exchange

 ionomer buffer layers is used to hold cations while managing water in local alkaline media. The second strategy

 involves pressurizing only the cathode side, resulting in a high local CO₂ concentration and enhancing the reverse

 osmosis phenomenon. The synergistic effects of these two strategies create an efficient microenvironment... ...

  Energy & Environmental Science

  January 2024  vol 17 : 6215-6224


“Breaking the current limitation of electrochemical CO₂

  reduction via a silica-hydroxide cycle”



   Chulwan Lim, Sangkuk Kim, Ji Hwan Song, Man Ho Han, Young-Jin Ko, Kwan-Young Lee,

   Jae-Young Choi, Woong Hee Lee, Hyung-Suk Oh.

   Abstract
    Alkaline local pH during a vigorous electrochemical CO₂ reduction reaction (CO₂RR) can improve the activity and
    selectivity of CO₂RR. However, it also leads to an alkalinity problem in that hydroxide ions obstruct the mass
    transfer of CO₂ to the active site, thereby limiting the current density. In this study, we introduce
    a silica-hydroxide cycle, which moderates the local pH by redistributing hydroxide ions, analogous to the
    carbonate-silicate cycle responsible for the drawdown of atmospheric CO₂ on Earth. In the membrane electrode
    assembly (MEA) of a CO₂ electrolyzer, SiO₂ undergoes weathering due to the high local pH and consequently
    consumes OH−, reducing the pH within the MEA. The dissolved silicate ions move to the membrane and... ...

  ACS ES&T Engineering

   Oct 2023  vol 3 : 1770-1786


“Room-Temperature Preparation of Platinized

  Nonstoichiometric Tungsten Oxide via Platinum

  Photodeposition Followed by Chemical Reduction:

  Kinetic Enhancement of Photocatalytic Oxidation and

  Disinfection under Low Intensity Visible-Light Irradiation”


   Jaesung Kim, Hongshin Lee, Minjeong Kim, Yong-Yoon Ahn, Young-Jin Ko, Hyung-Suk Oh,

   Minseok Kang, Myoung Won Chung, Seunghyun Weon, Min Cho, Hangil Lee, Jaesang Lee.

  Abstract
   Oxygen vacancy (OV) as the key site in promoting charge separation and visible-light harvesting in WO3 has often        been created through thermal annealing. However, this study proposes the sequential combination of Pt photode      position followed by chemical reduction using NaBH4 as a room-temperature approach to fabricate... ...

  Nano Energy

  June 2023  vol 110 :  108355


“Sb incorporated into oxides enhances stability in acid

  during the oxygen evolution reaction by inhibiting structural

  distortion”



    Young-Jin Ko, Chulwan Lim, Junyoung Jin, Min Gyu Kim, Ji Yeong Lee, Tae-Yeon Seong,

    Kwan-Young Lee, Byoung Koun Min, Jae-Young Choi, Taegeun Noh, Gyu Weon Hwang,

    Woong Hee Lee, Hyung-Suk Oh.

    Abstract
    Development of first-row transition-metal-based catalysts for oxygen evolution is a desirable goal due to the low
    cost and abundance of transition metals, relative to iridium. However, low stability of first-row transition metal
    catalysts in acidic electrolytes has impeded practical application. In this work, we proposed the role of Sb in 
    metal oxide which enhance electrochemical stability in acid media While a Co-Fe mixed oxide exhibited poor
    stability in acid, a FeCoSbOx electrode demonstrate superior stability of over 70 h under the same conditions... ...

  Journal of Materials Chemistry A

   Feb 2023  vol 11 : 5864-5872


“Electrochemically robust oxide supported dendritic Pt and Ir

  nanoparticles for highly effective polymer electrolyte

  membrane-unitized regenerative fuel cells ”


   Young-Jin Ko, Hyunchul Kim, Woong Hee Lee, Man Ho Han, Cheoulwoo Oh, Chang Hyuck Choi,

   Woong Kim, Jeong Min Baik, Jae-Young Choi, Peter Strasser, Hyung-Suk Oh

   Abstract
   Polymer electrolyte membrane-unitized regenerative fuel cells (PEM-URFCs) are promising energy storage and
   conversion systems. However, the dissolution of metal species due to frequent phase transformation and support
   corrosion at high voltages must be addressed. Herein, we design dendritic Pt (PtND) and Ir (IrND) combined with
   a robust oxide support (antimony doped tin oxide, ATO) for the oxygen electrode. Under ORR and OER potentials,
   a PtND–IrND/ATO catalyst produced lower average oxidation states of Pt and Ir than a Pt–Ir/C catalyst. 
   Consequently, the Pt and Ir dissolution of PtND–IrND/ATO derived from the phase transition was... ...

  Chemical Engineering Journal

  June 2023  vol 453 :  139826 (co-first author) 


“Strategies for CO₂ electroreduction in cation exchange

  membrane electrode assembly”



    Jaeyong Park, Young-jin Ko, Chulwan Lim, Hyunchul Kim, Byoung Koun Min, Kwan-Young Lee,

   Jai Hyun Koh, Hyung-Suk Oh, Woong Hee Lee

   Abstract
   For a CO₂ reduction reaction (CO₂RR), cation-exchange membrane (CEM)-based membrane electrode assembly
   (MEA) electrolyzers are among the most commercially viable systems; however, the acidic environment in these
   electrolyzers lowers the CO₂RR selectivity. Herein, we outline broad methods for enhancing the performance of
   CEM MEA electrolyzers by providing an alkaline environment for the cathode. An appropriate amount of anion
   exchange ionomer, high-alkali cation concentration, and thick catalyst layer with carbon increase the pH gradient
   for neutralization and minimize the neutralization boundary layer, thus turning most of the catalyst layer into an
   alkaline environment with high CO₂RR selectivity. To take advantage of cation effects, local cation concentrations       must be controlled to avoid losing energy efficiency due to high membrane resistance of large cations.... ...
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