• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.44-45
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• 2002

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.59-59
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• 2002

• 한국전기화학회:학술대회논문집
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• 2000.10a
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• pp.28-28
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• 2000

• Transactions on Electrical and Electronic Materials
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• v.13 no.4
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• pp.177-180
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• 2012

In this study, we prepared $LiFePO_4$- poly (sodium 4-styrenesulfonate) (PSS) composite by the hydrothermal method and ball-milling process. Different wt% PSS were added to $LiFePO_4$. The cathode electrodes were made from mixtures of $LiFePO_4$-PSS: SP-270: PVDF in a weighting ratio of 70%: 25%: 5%. $LiFePO_4$-PSS powders were characterized by X-ray diffraction (XRD), and scanning electron microscopy (SEM). The electrochemical properties of $LiFePO_4$-PSS/Li batteries were analyzed by cyclic voltammetry, charge/discharge tests, and AC impedance spectroscopy. A Li/$LiFePO_4$-PSS battery with 4.75 wt% PSS shows the best electrochemical properties, with a discharge capacity of 128 mAh/g.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.11
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• pp.843-847
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• 2010

This paper in concerned with the electrochemical properties for supercapacitor of composition with variation of super P/MWCNTs(multi-walled carbon nanotubes) contents. Electrochemical properties of the super P/MWCNTs were measured by cyclic voltammetry at the scan rates of 0.5 mV/s is $TEABF_4$(tetra-ethyl-ammonium-tetra-fluoro-borate) as electrolytes. As a result, the composition for 6 wt% content of MWCNTs led to an increase of capacitance, but DC resistance were decreased. It was found that the content and dispersion appearance of MWCNTs was attributed to the increase in capacitance and lower DC resistance.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.124-124
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• 2003

To improve the electrochemical properties of thin-film LiCoO$_2$ cathodes, metal oxides were coated on the LiCoO$_2$ thin films using f sputtering. Galvanostatic charge-discharge experiments showed the enhanced cycling behaviors in the metal-oxide coated LiCoO$_2$ thin films than the uncoated ones. These results are because the metal-oxide coating layer suppresses the degradation of Li-diffusion kinetics during cycling, which is related to the protection of cathode surface from the electrolytes [l-3]. The variation in the metal-oxide coating thickness ranging from 10 to 300 nm did not affect the electrochemical properties. Changes of lattice constants in the coated and bare LiCoO$_2$ thin films at different charged states will also be discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.214.1-214.1
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• 2011

In this work, the electrochemical properties of the surface treated multi-walled carbon nanotubes (MWNTs) are investigated for supercapacitors. Nitrogen- and oxygen functional groups containing MWNTs are prepared by nitrogen precursors and acidic treatment, respectively. The surface properties of the MWNTs are confirmed by X-ray photoelectron spectroscopy (XPS) and Zeta-potential measurements. The electrochemical properties of the MWNTs are investigated by cyclic voltammetry, impedance spectra, and charge-discharge cycling performance in 1 M $H_2SO_4$ at room temperature. As a result, these functionalized MWNTs lead to an increase in the specific capacitance as compared with the pristine MWNTs. It proposes that the pyridinic and pyridinic-N-oxides nitrogen species influence on the specific capacitance due to their positive charges, and thus an improved electron transfer at high current loads, since they are the most important functional groups affecting capacitive behaviors.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.1
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• pp.55-61
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• 2000

The electrochemical properties of hard carbon anodes in lithium ion batteries were improved by carbon coating using polyvinyl chloride (PVC). The reduction in irreversible capacity occured and the reversible capacity increased. It is suggested that the PVC carbon coating modifies the surface of hard carbon and reduces the surface reaction with species from air. The degree of the graphitization of PVC carbon was controlled by an addition of Ni, and the effect of the amount of Ni addition on the electrochemical properties was discussed.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.129-139
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• 2018

The effects of N doping concentration and dopant moieties on the electrochemical properties of nanoporous graphene and their dependence on annealing temperature are investigated. Four types of N moieties - amide, amine, graphitic-N, and oxidized-N - are obtained, which transformed into pyridinic-N and pyrrolic-N upon annealing. The diffusion coefficient (D') of the ions in the electrode is the maximum at $400^{\circ}C$ because of a high level of N doping, whereas the second highest D0 value is obtained at $700^{\circ}C$ owing to a high level of reduction and N doping. The highest specific capacitance is obtained for the sample annealed at $400^{\circ}C$.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.499-513
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• 2020

Among the many studies of carbon-based nanomaterials, carbon-based dots (CDs) have attracted considerable interest owing to their large surface area, intrinsic low-toxicity, excellent biocompatibility, high solubility, and low-cost with environmentally friendly routes, as well as their ability for modification with other nanomaterials. CDs have several applications in biosensing, photocatalysis, bioimaging, and nanomedicine. In addition, the fascinating electrochemical properties of CDs, including high active surface area, excellent electrical conductivity, electrocatalytic activity, high porosity, and adsorption capability, make them potential candidates for electrochemical sensing materials. This paper reviews the recent developments and synthesis of CDs and their composites for the proposed electrochemical sensing platforms. The electrochemical principles and future perspective and challenges of electrochemical biosensors are also discussed based on CDs-nanocomposites.