A5065897509- Advancements in Battery Materials
- Ecology and Conservation Studies
- Geology and Paleoclimatology Research
- Subcritical and Supercritical Water Processes
- Catalytic Processes in Materials Science
- Advanced Battery Materials and Technologies
- Supercapacitor Materials and Fabrication
- Phase Equilibria and Thermodynamics
- Coastal and Marine Dynamics
- Aeolian processes and effects
- Semiconductor materials and devices
- Coastal wetland ecosystem dynamics
- Hydrology and Sediment Transport Processes
- Soil erosion and sediment transport
- Marine and Coastal Research
- Catalysis and Oxidation Reactions
- Hydrology and Watershed Management Studies
- Pacific and Southeast Asian Studies
- Biodiesel Production and Applications
- Isotope Analysis in Ecology
- Environmental remediation with nanomaterials
- Mesoporous Materials and Catalysis
- Lubricants and Their Additives
- Crystallography and molecular interactions
- Advanced oxidation water treatment
Argonne National Laboratory
2012-2023
Alex's Lemonade Stand Foundation
2018
Seoul National University
2008-2016
Korea Fisheries Resources Agency
2010
Colorado State University
2010
Ajou University
2009
High-nickel content cathode materials offer high energy density. However, the structural and surface instability may cause poor capacity retention thermal stability of them. To circumvent this problem, nickel concentration-gradient have been developed to enhance high-nickel materials' cycling stability. Even though promising, fundamental mechanism concentration gradient's stabilization effect remains elusive because it is inseparable from nickel's valence gradient effect. isolate understand...
Manganese oxides, notably γ-MnO<sub>2</sub> and modified derivatives, have played a major role in electrochemical energy storage for well over century.
The pressing demand in electrical vehicle (EV) markets for high-energy-density lithium-ion batteries (LIBs) requires further increasing the Ni content high-Ni and low-Co cathodes. However, commercialization of cathodes is hindered by their intrinsic chemomechanical instabilities fast capacity fade. emerging single-crystalline strategy offers a promising solution, yet operation degradation mechanism remain elusive, especially extremely challenging ultrahigh-Ni (Ni > 90%) regime whereby phase...
The changes in hydraulic geometry of the Hwang River downstream Hapcheon Dam have been investigated since 1982. study reach is 45 km long from Re-regulation to confluence with Nakdong River, South Korea. geographic information system (GIS) analysis a time series aerial photographs taken 1982, 1993 and 2004 showed that non-vegetated active channel width decreased an average 152 m (47% reduction 1982). median bed material size increased 1.07 mm 1983 5.72 2003, slope 94 85 cm/km 2003. field...
The changes in channel geometry downstream of Hapcheon Dam, South Korea, are closely examined. Daily pulses water from peak hydropower generation and sudden sluice gate operations affect the 45-km reach Hwang River between Reregulation Dam Nakdong River. From 1983 to 2003, median bed-material size, d50, increased 1.0 5.7 mm, bed slope decreased 94 85 cm/km. vertical riverbed degradation averaged 2.6 m for a distance 20 km below reregulation dam. A simple analytical model is developed predict...
Abstract Ni‐rich cathode materials provide high energy density, but their structural and surface instability limits cyclability thermal stability. As one of the approaches to mitigate this problem, comprising high‐capacity core wrapped in Mn‐rich multiple shells are produced successfully. In contrast conventional batch‐type process for concentration‐gradient materials, a digital‐gradient cascade coprecipitation described here achieves improvements productivity quality consistency needed move...
Supercritical (sc) fluids are considered to be a promising alternative toxic organic solvents in variety of processes. In this work, study the synthesis terephthalic acid (TPA) from p-xylene (PX) using supercritical carbon dioxide (scCO2) as reaction medium was performed. The effects various process parameters were investigated, including temperature, residence time, and catalyst loading. maximum molar yield TPA that achieved less than 35%. oxidation for producing unfavorable under most...
Abstract We present a multi-proxy record (pollen, microscopic charcoal, magnetic susceptibility, carbon-isotopic composition, total organic carbon [TOC], carbon/nitrogen [C/N] ratios, and particle size) of the late Holocene environmental change human activities from Bongpo marsh on east coast Korea. Mutual interaction between environment humans during has not been properly investigated in Korea due to lack undisturbed samples with high sedimentation rates. In this study, history responses...
Abstract The episodic nature of coastal dune development has been widely identified in many areas over the world. What causes such episodicity is still hotly debated. Sea‐level change, climatic change and human impact have reported as main forcings, though there no agreement yet upon which factors are critical. This research provides some evidence that sea‐level fluctuation controlled building together, based optically stimulated luminescence (OSL) ages on west coast Korea. newly obtained...
The growing demand for lithium‐ion batteries to power electric vehicles and other energy‐dense devices continues fuel the need cathodes of increasingly higher nickel in cathodes. relentless pursuit high Ni content, however, raises concerns on compromising cell lifetime safety, especially under high‐voltage operation. Alternative traditional design uniform or core–shell composition, we report a rational control local stoichiometry high‐Ni cathodes, enabling their thermal cycling...