101 results match your criteria: "Korea Institute of Energy Technology KENTECH[Affiliation]"

Synergistic effect of Polydopamine incorporated Copper electrocatalyst by dopamine oxidation for efficient hydrogen production.

J Colloid Interface Sci

November 2023

Hydrogen Energy Technology Laboratory, Korea Institute of Energy Technology (KENTECH), 200 Hyeoksin-ro, Naju, Jeonnam 58330, Republic of Korea. Electronic address:

Tuning the metal-support interaction in electrocatalysts has been proposed as a viable method for manipulating the electronic structure and catalytic activity. In this work, inspired by natural hydrogenase enzyme, electrocatalysts with a hybrid metal-matrix complex using polydopamine (PDA) as a supporting matrix were synthesized for efficient green hydrogen production. Among the various Metal-PDA electrocatalysts, Cu-PDA shows outstanding catalytic activity (low overpotential (ƞ) of 104 mV at 10 mA cm and small Tafel slope of 60.

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The intestinal compartment ensures nutrient absorption and barrier function against pathogens. Despite decades of research on the complexity of the gut, the adaptive potential to physical cues, such as those derived from interaction with particles of different shapes, remains less understood. Taking advantage of the technological versatility of silica nanoparticles, spherical, rod-shaped, and virus-like materials were synthesized.

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Towards effective recovery of humate as green fertilizer from landfill leachate concentrate by electro-neutral nanofiltration membrane.

Sci Total Environ

October 2023

Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341000, China; Key Laboratory of Rare Earths, Chinese Academy of Sciences, Ganzhou 341000, China. Electronic address:

Under the environmental sustainability concept, landfill leachate concentrate can be up-cycled as a useful resource. Practical strategy for effective management of landfill leachate concentrate is to recover the existing humate as fertilizer purpose for plant growth. Herein, we designed an electro-neutral nanofiltration membrane to separate the humate and inorganic salts for achieving a sufficient humate recovery from leachate concentrate.

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Polar surfaces are intrinsically unstable and thus highly reactive due to the uncompensated surface charges. The charge compensation is accompanied by various surface reconstructions, establishing novel functionality for their applications. The present in situ atomic-scale electron microscopy study directly shows that the atomic step and step-assisted reconstruction play central roles in the charge compensation of polar oxide surfaces.

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The weight reduction of the bipolar plate (BP) is essential for commercializing unitized regenerative fuel cells (URFCs). In order to lighten the weight of the bipolar plate, we have used Pb/C composite powder as a cost-effective primary material, which is a mixture of low-density graphite and lead. Further, varied lead-carbon weight ratios (1: 8, 1:4, 1:1, 4:1, and 8:1) were investigated for fabricating the bipolar plate by hot-pressing process adding styrene-butadiene rubber (SBR) as a binder.

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Aqueous zinc-ion batteries (ZIBs) provide a safer and cost-effective energy storage solution by utilizing nonflammable water-based electrolytes. Although many research efforts are focused on optimizing zinc anode materials, developing suitable cathode materials is still challenging. In this study, one-dimensional, mixed-phase MnO nanorods are synthesized using ionic liquid (IL).

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Article Synopsis
  • Researchers created magnetic nanomaterials (NiCuDyFeO) with copper and dysprosium doping using a sol-gel auto-combustion method to study their ability to degrade methylene blue, conduct electrocatalytic water splitting, and exhibit antibacterial effects.
  • The nanomaterials showed a single-phase spinel cubic structure and a rise in saturation magnetization along with a slight decrease in coercivity as the doping levels increased, while the optical band gap decreased significantly, enhancing photocatalytic activity to 93.67% degradation of methylene blue under sunlight.
  • The electrocatalytic performance was analyzed, revealing effective hydrogen evolution and oxygen evolution reactions with specified current densities and voltages; additionally, the antibacterial tests
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Lower hardness than strength: The auxetic composite microstructure of limpet tooth.

Acta Biomater

August 2023

Chair of Materials Physics, Department Materials Science, Montanuniversität Leoben, Austria. Electronic address:

The limpet tooth is widely recognized as nature's strongest material, with reported strength values up to 6.5 GPa. Recently, microscale auxeticity has been discovered in the leading part of the tooth, providing a possible explanation for this extreme strength.

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Herein, by choosing few-nm-thin two-dimensional (2D) nanocrystals of MOF-5 containing in-planner square lattices as a modular platform, a crystal lattice-guided wet-chemical etching has been rationally accomplished. As a result, two attractive pore patterns carrying Euclidean curvatures; precisely, plus(+)-shaped and fractal-patterned pores via ⟨100⟩ and ⟨110⟩ directional etching, respectively, are regulated in contrast to habitually formed spherical-shaped random etches on MOF surface. In agreement with the theoretical calculations, a diffusion-limited etching process has been optimized to devise high-yield of size-tunable fractal-pores on the MOF surface that tenders for a compatibly high payload of catalytic Re -complexes using the existing large edge area once modified into a free amine-group-exposed inner pore surface.

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MnO-Induced Oxidation of Iodide in Frozen Solution.

Environ Sci Technol

April 2023

KENTECH Institute for Environmental & Climate Technology, Korea Institute of Energy Technology (KENTECH), Naju 58330, Korea.

Metal oxides play a critical role in the abiotic transformation of iodine species in natural environments. In this study, we investigated iodide oxidation by manganese dioxides (β-MnO, γ-MnO, and δ-MnO) in frozen and aqueous solutions. The heterogeneous reaction produced reactive iodine (RI) in the frozen phase, and the subsequent thawing of the frozen sample induced the gradual transformation of in situ-formed RI to iodate or iodide, depending on the types of manganese dioxides.

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ConspectusEmploying semiconductor materials is a popular engineering method to harvest solar energy, which is widely investigated for photocatalysis (PC) and photoelectrocatalysis (PEC) that convert solar light to chemical energy. In particular, environmental photo(electro)catalysis has been extensively studied as a sustainable method for water treatment, air purification, and resource recovery. Environmental PC/PEC processes working in ambient conditions are initiated mainly through hole transfer to water (water oxidation) and electron transfer to dioxygen (O reduction) and the subsequent photoredox transformation of water and dioxygen serves as a base of various PC/PEC systems.

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Development of High-Performance Polymer Electrolyte Membranes through the Application of Quantum Dot Coatings to Nafion Membranes.

ACS Appl Mater Interfaces

March 2023

Organic Material Synthesis Laboratory, Department of Chemistry, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea.

Proton exchange membrane water electrolysis (PEMWE) generates oxygen and hydrogen at the anode and cathode, respectively, by conducting protons generated at the anode to the cathode through a proton exchange membrane (PEM). The performance of PEMWE can be improved with faster catalytic reactions at each electrode; thus, the development of a PEM with excellent ionic conductivity and physicochemical stability is essential. Nafion, a type of perfluoro-sulfonic acid polymer, is the most widely used PEM material.

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The utilization of bio-wastes, such as shaddock peels, is of great significance for sustainable development. Combined with the potential of peroxymonosulfate (PMS) based advanced oxidation process (AOP) in wastewater treatment, a highly efficient functional catalyst, derived from shaddock peels biochar (SPC) and embedded with CoO@Co nanoparticles, i.e.

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Production of polyhydroxyalkanoate (PHA) copolymer from food waste using mixed culture for carboxylate production and Pseudomonas putida for PHA synthesis.

J Environ Manage

June 2023

Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada; KENTECH Institute for Environmental and Climate Technology, Korea Institute of Energy Technology (KENTECH) 200 Hyeoksin-ro, Naju-si, Jeollanam-do, Republic of Korea. Electronic address:

Production of polyhydroxyalkanoates (PHAs) with high concentration of carboxylate, that was accumulated from solid state fermentation (SSF) of food waste (FW), was tested using Pseudomonas putida strain KT2440. Mixed-culture SSF of FW supplied in a high concentration of carboxylate, which caused a high PHA production of 0.56 g PHA/g CDM under nutrients control.

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Hydrogen has become an indispensable aspect of sustainable energy resources due to depleting fossil fuels and increasing pollution. Since hydrogen storage and transport is a major hindrance to expanding its applicability, green ammonia produced by electrochemical method is sourced as an efficient hydrogen carrier. Several heterostructured electrocatalysts are designed to achieve significantly higher electrocatalytic nitrogen reduction (NRR) activity for electrochemical ammonia production.

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Relatively low rate of electron recovery is one of the factors that limit the advancement of bioelectrochemical systems. Here, new periodic polarizations were investigated with electroactive biofilms (EABs) enriched from activated sludge and Geobacter sulfurreducens biofilms. When representative anode potentials (E ) were applied, redox centers with midpoint potentials (E ) higher than E were identified by localized cyclic voltammetry.

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Tuning the selectivity of CO hydrogenation is of significant scientific interest, especially using nickel-based catalysts. Fundamental insights into CO hydrogenation on Ni-based catalysts demonstrate that CO is a primary intermediate, and product selectivity is strongly dependent on the oxidation state of Ni. Therefore, modifying the electronic structure of the nickel surface is a compelling strategy for tuning product selectivity.

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To achieve a zero-carbon-emission society, it is essential to increase the use of clean and renewable energy. Yet, renewable energy resources present constraints in terms of geographical locations and limited time intervals for energy generation. Therefore, there is a surging demand for developing high-performance energy storage systems (ESSs) to effectively store the energy during the peak time and use the energy during the trough period.

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Electrocatalytic CO reduction reaction (CORR) is greatly facilitated by Au surfaces. However, large fractions of underlying Au atoms are generally unused during the catalytic reaction, which limits mass activity. Herein, we report a strategy for preparing efficient electrocatalysts with high mass activities by the atomic-level transplantation of Au active sites into a Ni nanocluster (NC).

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The concentration of guest elements (dopants) into host materials play an important role in changing their intrinsic electrical and optical properties. The existence of hetero-element induce defect in crystal structure, affecting conductivity. In the current work, we report Cu ion into hematite in the defectronics point of view and their photoelectrochemical properties.

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Materials displaying negative Poisson's ratio, referred to as auxeticity, have been found in nature and created in engineering through various structural mechanisms. However, uniting auxeticity with high strength and high stiffness has been challenging. Here, combining in situ nanomechanical testing with microstructure-based modeling, we show that the leading part of limpet teeth successfully achieves this combination of properties through a unique microstructure consisting of an amorphous hydrated silica matrix embedded with bundles of single-crystal iron oxide hydroxide nanorods arranged in a pseudo-cholesteric pattern.

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Manipulating wettability of catalytic surface for improving ammonia production from electrochemical nitrogen reduction.

J Colloid Interface Sci

March 2023

Hydrogen Energy Technology Laboratory, Korea Institute of Energy Technology (KENTECH), 200 Hyeoksin-ro, Naju, Jeonnam 58330, Rep. of Korea; Research Institute, NEEL Sciences, INC., 58326 Jeollanamdo, South Korea; Center for Energy Storage System, Chonnam National University, Gwangju 61186, South Korea. Electronic address:

An electrochemical nitrogen reduction reaction (ENRR) is considered a promising alternative for the traditional Haber-Bosch process. In this study, we present a method for improving the ENRR by controlling the wettability of the catalyst surface, suppressing the hydrogen evolution reaction (HER) while facilitating N adsorption. Reduced-graphene oxide (rGO) with a hydrophobic surface property and a contact angle (C.

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In the present report, we synthesized highly porous 1D nanobelt-like cobalt phosphate (CoPO) materials using a hydrothermal method for supercapacitor (SC) applications. The physicochemical and electrochemical properties of the synthesized 1D nanobelt-like CoPO were investigated using X-ray diffraction (XRD), X-ray photoelectron (XPS) spectroscopy, and scanning electron microscopy (SEM). The surface morphology results indicated that the deposition temperatures affected the growth of the 1D nanobelts.

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Heterogeneous structures containing highly dispersed semiconductor nanoparticles on a photoactive support are effective for the photocatalytic hydrogen evolution reaction (HER). In this work, the interlayer ion-exchange and space confining nature of layered titanate nanosheets was used to embed copper ions in titanates, which were then transitioned to mesoporous CuO/TiO with highly dispersed CuO nanostructures. Both experimental and density functional theory (DFT) studies demonstrated that the fine-decoration of CuO nanostructures and the reducible valence of the copper species enabled stable superior photocatalytic activity.

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An integrated leachate bed reactor - anaerobic membrane bioreactor system (LBR-AnMBR) for food waste stabilization and biogas recovery.

Chemosphere

January 2023

Dept Civil & Environmental Engineering, University of Waterloo 200 University Ave W, Waterloo, Ontario, Canada, N2L 3G1; KENTECH Institute for Environmental and Climate Technology, Korea Institute of Energy Technology (KENTECH), 200 Hyeoksin-ro, Naju, 58330, Republic of Korea. Electronic address:

This study developed an integrated LBR - AnMBR system for efficient stabilization and biogas recovery from food waste (FW) at room temperatures (21-22 °C). First, the leachate recirculation rate (4.4-13.

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