Publications de Youngdon Ko | EPFL Graph Search

All Platinum Group Metal-Free and Durable Catalysts for Direct Borohydride Fuel Cells

Thi Ha My Pham, Andreas Züttel, Youngdon Ko, Victor Carle Adrien Boureau, Liping Zhong

Platinum group metal-free catalysts (e.g., Fe-N-C and Co-N-C) are used as hydrogen peroxide reduction reaction (PRR) catalysts in direct borohydride fuel cells (DBFCs). Fe-N-C is more active in the PRR and demonstrates high performance at the beginning of ...

Amer Chemical Soc2024

Solvent- and catalyst-free reduction of CO2 with ammonia borane

Andreas Züttel, Youngdon Ko, Liping Zhong

Ammonia borane (AB) has been extensively studied as a solid-state hydrogen storage material. On the other hand, its reactivity with CO2 is still unclear, especially in the solid state. By carefully controlling the CO2 pressure and temperature, AB efficient ...

Royal Soc Chemistry2024

Understanding the role of surface oxygen-containing functional groups on carbon-supported cobalt catalysts for the oxygen evolution reaction

Thi Ha My Pham, Andreas Züttel, Youngdon Ko, Kangning Zhao, Liping Zhong, Manhui Wei

Supported Co-based catalysts exhibit promising catalytic activities in the oxygen evolution reaction (OER) during alkaline water electrolysis. Surface functionalization of the support modulates the dispersion of the catalysts and their interaction with the ...

Royal Society of Chemistry2023

Graphene nanoplatelets promoted CoO-based catalyst for low temperature CO2 methanation reaction

Thi Ha My Pham, Andreas Züttel, Youngdon Ko, Liping Zhong

Methanation of CO2 is an important reaction for reducing CO2 emissions in a power-to-gas system. Compared to cobalt supported on gamma-Al2O3, cobalt supported on graphene nanoplatelets (GNPs) showed significantly better performance for CO2 methanation. Cob ...

FRONTIERS MEDIA SA2023

Elucidating the Mechanism of Fe Incorporation in In Situ Synthesized Co-Fe Oxygen-Evolving Nanocatalysts

Thi Ha My Pham, Andreas Züttel, Vasiliki Tileli, Tzu-Hsien Shen, Youngdon Ko, Liping Zhong

Ni- and Co-based catalysts with added Fe demonstrate promising activity in the oxygen evolution reaction (OER) during alkaline water electrolysis, with the presence of Fe in a certain quantity being crucial for their enhanced performance. The mode of incor ...

Amer Chemical Soc2023

Using Complex Hydrides for Hydrogen Storage and Direct Borohydride Fuel Cells for Electricity Production

Youngdon Ko

Hydrogen storage and utilization are the technologies to achieve carbon-neutral energy systems with renewable energy sources. Among the various materials that have been investigated, complex hydrides are a material exhibiting high gravimetric hydrogen dens ...

EPFL2023

Tandem effect of Ag@C@Cu catalysts enhances ethanol selectivity for electrochemical CO2 reduction in flow reactors

Thi Ha My Pham, Andreas Züttel, Wen Luo, Jie Zhang, Mo Li, Youngdon Ko, Cedric David Koolen, Liping Zhong

CO-selective metals (e.g., Ag) on Cu catalysts improve the selec-tivity of multi-carbon (C2+) products in electrochemical CO2 reduc-tion. However, the origin of the improvement remains unclear due to the convolution of tandem and interface effects. Here, A ...

ELSEVIER2022

Selective Borohydride Oxidation Reaction on Nickel Catalyst with Anion and Cation Exchange Ionomer for High-Performance Direct Borohydride Fuel Cells

Thi Ha My Pham, Loris Giovanni Lombardo, Andreas Züttel, Heena Yang, Mo Li, Youngdon Ko

Direct borohydride fuel cells (DBFCs) operate with liquid H2O2 and a high-energy-density NaBH4 solution. A facile, direct synthesis method using a non-noble nickel catalyst for the DBFC anode is shown. The complex anode reaction with an anion-exchange iono ...

WILEY-V C H VERLAG GMBH2022

Support-Dependent Cu-In Bimetallic Catalysts for Tailoring the Activity of Reverse Water Gas Shift Reaction

Thi Ha My Pham, Kun Zhao, Wen Luo, Mo Li, Youngdon Ko, Liping Zhong

Cu-based bimetallic catalysts have attracted great attention for the reverse water gas shift (RWGS) reaction due to their high activity and selectivity. This work reports the application of Cu-In bimetallic catalysts for the RWGS reaction and demonstrates ...

AMER CHEMICAL SOC2022

Direct CO2 Capture and Reduction to High-End Chemicals with Tetraalkylammonium Borohydrides

Loris Giovanni Lombardo, Andreas Züttel, Kun Zhao, Heena Yang, Youngdon Ko

We demonstrate the ability of tetraalkylammonium borohydrides to capture large amounts of CO2, even at low CO2 concentrations, and reduce it to formate under ambient conditions. These materials show CO2 absorption capacities up to 30 mmolCO2 g(-1) at room ...

Wiley-VCH Verlag GmbH2021

Interfacial Effect between Aluminum-Based Complex Hydrides and Nickel-Containing Porous Carbon Sheets

Emad Oveisi, Loris Giovanni Lombardo, Andreas Züttel, Heena Yang, Mo Li, Youngdon Ko

Supported aluminum-based complex hydrides (alanates) were investigated in view of their interaction at the interface. Nickel-containing porous carbon sheets (Ni-PCSs) were combined with various alanates, resulting in a decrease of the decomposition tempera ...

AMER CHEMICAL SOC2020

Membrane electrode assembly fabricated with the combination of Pt/C and hollow shell structured-Pt-SiO2@ZrO2 sphere for self-humidifying proton exchange membrane fuel cell

Andreas Züttel, Heena Yang, Youngdon Ko

The Pt-supported hollow structured Pt-HZrO2 with the shell thickness of 27 nm is successfully synthesized. The water retention ability of Pt-HZrO2 is significantly enhanced compared with that of SiO2@ZrO2 due to the hydrophilic hollow structured HZrO2 with ...

Elsevier2017

Effect of Boron Doping On Graphene Oxide for Ammonia Adsorption

Andreas Züttel, Heena Yang, Youngdon Ko

Boron doped graphene oxide (B-GO) is a highly effective adsorbent for ammonia due to the high density of strong Lewis acid sites arising from the boron. GO was doped by various amounts of boron described as xB-GO (x= 1.0, 3.0, and 5.0). B-GO was successful ...

Wiley-V C H Verlag Gmbh2017