A5046112894- Supercapacitor Materials and Fabrication
- Iron oxide chemistry and applications
- Advanced Photocatalysis Techniques
- Advancements in Battery Materials
- Graphene research and applications
- Electrocatalysts for Energy Conversion
- Advanced Battery Materials and Technologies
- Advanced battery technologies research
- Advanced Sensor and Energy Harvesting Materials
- Copper-based nanomaterials and applications
- Quantum Dots Synthesis And Properties
- Advancements in Photolithography Techniques
- Nanofabrication and Lithography Techniques
- Membrane Separation Technologies
- Mine drainage and remediation techniques
- Conducting polymers and applications
- TiO2 Photocatalysis and Solar Cells
- Solar-Powered Water Purification Methods
- Synthesis and properties of polymers
- Gold and Silver Nanoparticles Synthesis and Applications
- Solar Thermal and Photovoltaic Systems
- Advanced Battery Technologies Research
- Electrochemical Analysis and Applications
- Fuel Cells and Related Materials
- MXene and MAX Phase Materials
Ulsan National Institute of Science and Technology
2016-2025
Korea University
2025
Samsung (South Korea)
2018-2021
Ulsan College
2015-2020
Government of the Republic of Korea
2015-2020
Institute for Basic Science
2015-2018
University of California, San Diego
2018
University of California System
2018
Seoul National University
2014
Seoul Medical Center
2012
NiO nanostructures with three distinct morphologies were fabricated by a sol–gel method and their morphology-dependent supercapacitor properties exploited. The nanoflower- shaped distinctive three-dimensional (3D) network the highest pore volume shows best properties. nanopores in flower-shaped nanostructures, offering advantages contact transport of electrolyte, allow for 3D nanochannels structure, providing longer electron pathways. XPS EIS data nanostructure confirm that NiO, which has...
A mass-producible mesoporous graphene nanoball (MGB) was fabricated via a precursor-assisted chemical vapor deposition (CVD) technique for supercapacitor application. Polystyrene balls and reduced iron created under high temperature hydrogen gas environment provide solid carbon source catalyst growth during the CVD process, respectively. Carboxylic acid sulfonic functionalization of polystyrene ball facilitates homogeneous dispersion hydrophobic polymer template in metal precursor solution,...
The hybrid device, screen-printed on two sides of the fabric, is designed to scavenge biochemical energy from wearer's sweat using a biofuel cell module, and store harvested bioenergy into supercapacitor module for subsequent use.
Abstract Despite their safety, nontoxicity, and cost‐effectiveness, zinc aqueous batteries still suffer from limited rechargeability poor cycle life, largely due to spontaneous surface corrosion formation of large Zn dendrites by irregular uneven plating stripping. In this work, these untoward effects are minimized covering electrodes with ultrathin layers covalent organic frameworks, COFs. These nanoporous mechanically flexible films form self‐assembly—via the straightforward scalable...
Abstract Utilizing the broad‐band solar spectrum for sea water desalination is a promising method that can provide fresh without sophisticated infrastructures. However, solar‐to‐vapour efficiency has been limited due to lack of proper design evaporator deal with either large amount heat loss or salt accumulation. Here, these issues are addressed via two cost‐effective approaches: I) rational concave shaped supporter by 3D‐printing promote light harvesting capacity multiple reflections on...
This review systematically explores various strategies aimed at enhancing charge transfer different levels—bulk, surface, and interfaces of hematite. The examination encompasses diverse approaches, assesses their impact on mitigating the identified issues.
Solar desalination via thermal evaporation of seawater is one the most promising technologies for addressing serious problem global water scarcity because it does not require additional supporting energy other than infinite solar generating clean water. However, low efficiency and a large amount heat loss are considered critical limitations technology. The combination mesoporous three-dimensional graphene networks (3DGNs) with high absorption property water-transporting wood pieces...
We report a novel approach to synthesize chemical vapor deposition-grown three-dimensional graphene nano-networks (3D-GNs) that can be mass produced with large-area coverage. Annealing of PVA/iron precursor under hydrogen environment, infiltrated into 3D-assembled-colloidal silicas reduces iron ions and generates few-layer by precipitation carbon on the surface. The 3D-GN grown any electronic device-compatible substrate, such as Al2O3, Si, GaN, or Quartz. conductivity surface area are 52...
A microwave-assisted hydrothermal synthesis produces ZnFe2 O4 containing Na residue as a precursor to CO2 hydrogenation catalyst that displays high conversion and selectivity liquid hydrocarbon products in the gasoline diesel range with olefin-to-paraffin ratios. Compared reference catalysts derived from Fe2 O3 ZnO-Fe2 physical mixture, -derived contains well-dispersed iron particles Zn serving structural promoter. profound effect of residual an electronic promoter is also observed, which...
We report a robust and direct route to fabricate three-dimensional nano-foam of few-layer graphene (3D-NFG) with large area coverage via chemical vapor deposition (CVD) technique. Pyrolysis polymer/nickel precursor film under hydrogen environment, simply prepared by spin-coating, leads the creation in reduction process nickel ions. Carbonized-C nano-frame formed from pyrolysis are used as solid carbon source catalyst for growth CVD conditions, respectively. investigate use 3D-NFG, advantage...
This work has been performed to determine the critical size of GeO2 nanoparticle for lithium battery anode applications and identify its quantum confinement related effects on electrochemical performance. nanoparticles with different sizes ∼ 2, 6, 10, 35 nm were prepared by adjusting reaction rate, controlling temperature reactant concentration, using solvents. Among nanoparticles, 6 sized showed best Unexpectedly smaller particles 2 inferior performances compared those one. was due low...
A highly-porous, binder free 3D-NiCo<sub>2</sub>O<sub>4</sub>/Ni nanostructure on the Ni-wire was fabricated for flexible fiber supercapacitors. The device exhibited enhanced capacitance, high efficiency, good cycling stability, and flexibility.
To boost the photoelectrochemical water oxidation performance of hematite photoanodes, high temperature annealing has been widely applied to enhance crystallinity, improve interface between hematite-substrate interface, and introduce tin-dopants from substrate. However, when using additional dopants, interaction unintentional tin intentional dopant is poorly understood. Here, germanium, we investigate how diffusion affects overall in germanium:tin co-doped systems. After revealing that...
This study introduces an in situ fabrication of nanoporous hematite with a Ti-doped SiOx passivation layer for high-performance water-splitting system. The (Ti-(SiOx /np-Fe2 O3 )) has photocurrent density 2.44 mA cm(-2) at 1.23 VRHE and 3.70 1.50 . When cobalt phosphate co-catalyst was applied to Ti-(SiOx ), the reached 3.19 stability, which shows great potential use synergistic effect decreased charge recombination, increased number active sites, reduced hole-diffusion pathway from electrolyte.
Abstract Stretchable electronics are considered as next‐generation devices; however, to realize stretchable electronics, it is first necessary develop a deformable energy device. Of the various components in devices, fabrication of current collectors crucial because they must be mechanically robust and have high electrical conductivity under deformation. In this study, authors present conductive polymer composite composed Jabuticaba‐like hybrid carbon fillers containing nanotubes black...
In this report, we show that by creating a nanoporous haematite (α-Fe2O3) structure using boric acid (H3BO3) treatment, the chronic issue of short diffusion length carriers in α-Fe2O3 for photoelectrochemical (PEC) applications can be successfully addressed. The slow release Fe3+ ions because presence H3BO3 leads to creation smaller dimension FeOOH nanorods, composed ∼15 nm domains. suppresses recombination providing facile extraction holes from surface favorably sized optimized sample...
Abstract Nano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the designs with higher concentrations remain be commercialized despite recent remarkable progress. One of most critical issues fundamental understanding lithium–silicon Coulombic efficiency. Particularly, this key resolve subtle yet accumulatively significant alterations efficiency by various paths processes over cycles. Here, we provide quantitative and...
We report that metal ions (M: Sn4+ and Ti4+) boron-codoped hematite photoanodes with an n–n+ homojunction showed significantly increased photoelectrochemical (PEC) water splitting activity greatly reduced surface recombination. The secondary B-doping of broadly used M-doped not only suppresses the number M+ ions, which inevitably cause electron–hole pair (EHP) recombination, but also generates internal electric field for easy hole extraction. Taking advantage these effects, maximum length...
Doping engineering is of key importance for controlling the electrical, optical, and structural properties a semiconductor. In more expanded doping systems, codoping with deep insight understanding interactions between impurities necessary to make an efficient photoelectrode. Here, we show that high formation energy Si-doped hematite can be decreased introduction host Ti-dopant, making easy cost-efficient solution-based Si possible. The effect positive interaction dopants lowers in standard...
We explore the potential of employing diketopyrrolopyrrole (DPP) based π-conjugated OSs as a hole transport layer material in heteroatom-doped hematite (Ti–Fe2O3/Ge–Fe2O3) photoanodes for efficient photoelectrochemical water splitting. The siloxane-modified polymer (PSi) with high carrier mobility and crystallinity revealed great to extract holes by forming built-in while showing stability an alkaline electrolyte oxidation. Because easy extraction subsequent fast property PSi interlayer...
Over the past few decades, extensive research on photoelectrochemical (PEC) water splitting has been conducted as a promising solution to meet increasing demand for cleaner and renewable energy in sustainable manner.
The photoelectrochemical (PEC) water oxidation reaction on hematite photoanodes poses challenges, notably the limited hole diffusion length and poor electrical properties. This study addresses these issues by creating a highly porous structure through Kirkendall effect at interface of overlayer precursor. By fabricating branched precursors, we produced nanoporous with an average strut diameter below 10 nm between pores. Coupled morphological engineering, doping from enhances properties...
Electrochemical water splitting involving two-half chemical cell reactions is a promising approach to generate hydrogen and oxygen. Although this method sustainable, the sluggish kinetics of oxygen evolution reaction (OER) occurring at anode due high overpotential an issue be addressed. Recently, various structural engineering approaches have been explored improve efficiency OER by reducing overpotential. Among them, incorporating noble metals into electrodes doping or creating...