A5084410026- Electrocatalysts for Energy Conversion
- Fuel Cells and Related Materials
- Advanced battery technologies research
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Supercapacitor Materials and Fabrication
- Conducting polymers and applications
- Electrochemical Analysis and Applications
- Advanced Photocatalysis Techniques
- TiO2 Photocatalysis and Solar Cells
- Catalytic Processes in Materials Science
- Transition Metal Oxide Nanomaterials
- Advanced Battery Technologies Research
- Gas Sensing Nanomaterials and Sensors
- Advancements in Solid Oxide Fuel Cells
- Quantum Dots Synthesis And Properties
- Extraction and Separation Processes
- Molecular Junctions and Nanostructures
- Semiconductor materials and devices
- Membrane-based Ion Separation Techniques
- Advanced Nanomaterials in Catalysis
- Hybrid Renewable Energy Systems
- Graphene research and applications
- Perovskite Materials and Applications
- Catalysis and Hydrodesulfurization Studies
Seoul National University
2016-2025
Institute for Basic Science
2016-2025
Pohang University of Science and Technology
2004-2024
Seoul St. Mary's Hospital
2023
Catholic University of Korea
2023
Government of the Republic of Korea
2015-2021
Seoul Institute
2017-2020
Southern Nazarene University
2015
Korea Institute of Science and Technology
2011-2015
Humboldt-Universität zu Berlin
2013
Electrooxidation of methanol in sulfuric acid solution was studied using Pt, Pt/Ni(1:1 and 3:1), Pt/Ru/Ni(5:4:1 6:3.5:0.5), Pt/Ru(1:1) alloy nanoparticle catalysts, relation to oxidation processes the direct fuel cell. The Pt/Ni Pt/Ru/Ni alloys showed excellent catalytic activities compared those pure Pt Pt/Ru. role Ni as a catalytically enhancing agent process interrogated cyclic voltammetry, chronoamperometry, X-ray photoelectron spectroscopy, transmission electron microscopy, diffraction....
Si composite negative electrodes for lithium secondary batteries degrade in the dealloying period with an abrupt increase internal resistance that is caused by a breakdown of conductive network made between and carbon particles. This results from volume contraction particles after expansion previous alloying process. Due to large resistance, reaction not completed while remains as lithiated state. The anodic performance greatly improved either applying pressure on cells or loading larger...
Demand on the practical synthetic approach to high performance electrocatalyst is rapidly increasing for fuel cell commercialization. Here we present a synthesis of highly durable and active intermetallic ordered face-centered tetragonal (fct)-PtFe nanoparticles (NPs) coated with "dual purpose" N-doped carbon shell. Ordered fct-PtFe NPs size only few nanometers are obtained by thermal annealing polydopamine-coated PtFe NPs, shell that in situ formed from dopamine coating could effectively...
Hollowing Out Metal Oxide Nanoparticles Corrosion is normally a problem, but it can be useful, for example, when you wish to create hollow metal nanoparticles, whereby the reduction of one species in solution drives dissolution core particle. Oh et al. (p. 964 ; see Perspective by Ibáñez and Cabot ) adapted this approach oxide nanoparticles placing Mn 3 O 4 nanocrystals with Fe 2+ ions, which replaces nanocrystal exterior γ-Fe 2 . At sufficiently high concentrations, nanocages formed. These...
A highly active and stable non-Pt electrocatalyst for hydrogen production has been pursued a long time as an inexpensive alternative to Pt-based catalysts. Herein, we report simple effective approach prepare high-performance iron phosphide (FeP) nanoparticle electrocatalysts using oxide nanoparticles precursor. single-step heating procedure of polydopamine-coated leads both carbonization polydopamine coating the carbon shell phosphidation FeP, simultaneously. Carbon-shell-coated FeP show low...
The effect of porous structures on the electrocatalytic activity N-doped carbon is studied by using electrochemical analysis techniques and result applied to synthesize highly active stable Fe-N-C catalyst for oxygen reduction reaction (ORR). We developed synthetic procedures prepare three types model catalysts that are designed systematic comparison structures. difference in their catalytic investigated relation surface area parameters. found macro- mesoporous contribute different stages...
Developing high‐energy‐density electrodes for lithium ion batteries (LIBs) is of primary importance to meet the challenges in electronics and automobile industries near future. Conversion reaction‐based transition metal oxides are attractive candidates LIB anodes because their high theoretical capacities. This review summarizes recent advances on development nanostructured use battery based conversion reactions. The oxide materials covered this include iron, manganese, cobalt, copper,...
Dye-sensitized solar cells (DSSCs) comprising chemically synthesized nanorods and nanoparticles are investigated. In identical circumstances, except for the charge-collection efficiency, nanorod-based DSSCs show improved photovoltaic properties (6.2 % versus 4.3 NP-based DSSCs) owing to characteristics of slightly enhanced electron transport predominantly degraded charge recombination, compared with nanoparticle-based DSSC.
Although different kinds of metal oxide nanoparticles continue to be proposed as anode materials for lithium ion batteries (LIBs), their cycle life and power density are still not suitable commercial applications. Metal have a large storage capacity, but they suffer from the excessive generation solid–electrolyte interphase (SEI) on surface, low electrical conductivity, mechanical degradation pulverization resulted severe volume expansion during cycling. Herein we present preparation...
The capacity limitations of insertion‐compound cathodes has motivated interest in a sulfur cathode for rechargeable battery cell with metallic‐lithium anode; but irreversible loss owing to solubility intermediate Li 2 S x (x = 2–8) polysulfides the organic‐liquid electrolytes used prevented practical application. A dual‐function structure consisting layered tungsten disulfide (WS ) supported both on current collector and carbon cloth interlayer (CCl) gives excellent performance lithium...
Methanol is a promising fuel for direct methanol cells in portable devices. A deeper understanding of its electro-oxidation needed evaluating electrocatalytic performance and catalyst design. Here we provide an in-depth investigation the cyclic voltammetry (CV) electro-oxidation. The oxidation peak backward scan shown to be unrelated residual intermediate oxidation. origin second (If2) expected on Pt–Ox. Electrochemical impedance spectroscopy coupled with CV reveals hysteresis shift...
Sulfur-rich copolymers based on poly(sulfur-random-1,3-diisopropenylbenzene) (poly(S-r-DIB)) were synthesized via inverse vulcanization to create cathode materials for lithium-sulfur battery applications. These exhibit enhanced capacity retention (1005 mAh/g at 100 cycles) and lifetimes over 500 cycles a C/10 rate. poly(S-r-DIB) represent new class of polymeric electrode that one the highest charge capacities reported, particularly after extended charge-discharge cycling in Li-S batteries.
Edge-exposed MoS2 nano-assembled structures are designed for high hydrogen evolution reaction activity and long term stability. The number of sulfur edge sites spheres sheets is confirmed by Raman spectroscopy EXAFS analysis. By controlling the morphology with formation assembly small-size fragments MoS2, resulting assembled have electrocatalytic HER thermodynamic
The design of electrocatalysts for polymer electrolyte membrane fuel cells must satsify two equally important fundamental principles: optimization electrocatalytic activity and long-term stability in acid media (pH <1) at high potential (0.8 V). We report here a solution-based approach to the preparation Pt-based alloy with early transition metals realistic parameters Pt3M (M = Y, Zr, Ti, Ni, Co) nanocatalysts oxygen reduction reaction (ORR). enhanced ORR relationship between electronic...
The electrochemical synthesis of NH3 by the nitrogen reduction reaction (NRR) at low temperature (<65 °C) and atmospheric pressure using nanosized γ-Fe2O3 electrocatalysts were demonstrated. activity selectivity catalyst was investigated both in a 0.1 M KOH electrolyte when incorporated into an anion-exchange membrane electrode assembly (MEA). In half-reaction experiment conducted electrolyte, presented faradaic efficiency 1.9% weight-normalized 12.5 nmol h–1 mg–1 0.0 VRHE. However, toward...
Electrochemical production of H2O2 from O2 is a promising alternative to the energy-intensive anthraquinone process that currently used as an industry standard. Although most research on oxygen reduction reaction (ORR) has focused 4-electron pathway water relevant fuel cells, 2-electron ORR produce also significant commercial interest. The first half this Perspective deals with progress made in developing noble metal, carbon-based, and single-atom electrocatalysts highlights design...
An aryl ether-free less-phenyl adsorbing poly-carbazole-based polymer shows superior performance and durability for anion exchange membrane fuel cells electrolyzers.
Compared to nanostructured platinum (Pt) catalysts, ordered Pt-based intermetallic nanoparticles supported on a carbon substrate exhibit much enhanced catalytic performance, especially in fuel cell electrocatalysis. However, direct synthesis of homogeneous alloy nanocatalysts carbonaceous supports with high loading is still challenging. Herein, we report novel synthetic strategy directly produce highly dispersed MPt (M = Fe, Co, or Ni) various catalyst loading. Importantly, unique bimetallic...
Ultra-stable Pt cathode catalysts in ultra-low loading proton exchange membrane fuel cells were synthesized by facile carbon encapsulation.