• Carbon letters
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• v.27
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• pp.1-11
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• 2018

A simple, but effective means of tailoring the physical and chemical properties of carbon materials should be secured. In this sense, chemical doping by incorporating boron or nitrogen into carbon materials has been examined as a powerful tool which provides distinctive advantages over exohedral doping. In this paper, we review recent results pertaining methods by which to introduce boron atoms into the $sp^2$ carbon lattice by means of high-temperature thermal diffusion, the properties induced by boron doping, and promising applications of this type of doping. We envisage that intrinsic boron doping will accelerate both scientific and industrial developments in the area of carbon science and technology in the future.

• Carbon letters
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• v.8 no.3
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• pp.214-224
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• 2007

The field of photocatalysis is one of the fastest growing areas both in research and commercial fields. Titanium dioxide is the most investigated semi-conductor material for the photocatalysis applications. Research to achieve $TiO_2$ visible light activation has drawn enormous attentions because of its potential to use solar light. This paper reviews the attempts made to extend its visible photocatalytic activity by carbon doping. Various approaches adopted to incorporate carbon to $TiO_2$ are summarized highlighting the major developments in this active research field. Theoretical features on carbon doping are also presented. Future scenario in the rapidly developing and exciting area is outlined for practical applications with solar light.

• Progress in Superconductivity and Cryogenics
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• v.24 no.4
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• pp.55-58
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• 2022

Carbon-based doping to MgB₂ superconductor is the simplest approach to enhance the critical current densities under magnetic fields. Carbon quantum dots is synthesized in this work as a carbon provider to MgB₂ superconductors. Polyvinyl Pyrrolidone is pyrolyzed and dispersed in dimethylfomamide solvent as a dopant to the mixture of Mg and B powders. Doped MgB₂ bulk samples clearly show the decrease of a-axis lattice constant, grain refinements, and broadening of FWHM of diffraction peaks compared to un-doped MgB₂ possibly due to the carbon substitution and/or boron vacancy at the boron site in MgB₂ lattice. Also, high-field J_c for the doped MgB₂ is enhanced significantly with the crossover about 3 T at 5 & 20 K when increasing the doping of carbon quantum dots.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2029-2035
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• 2013

The impact of phosphorous (P)-doping on the electrochemical performance and surface chemistry of soft carbon is investigated by means of galvanostatic cycling and ex situ X-ray photoelectron spectroscopy (XPS). P-doping plays an important role in storing more Li ions and discernibly improves reversible capacity. However, the discharge capacity retention of P-doped soft carbon electrodes deteriorated at $60^{\circ}C$ compared to non-doped soft carbon. This poor capacity retention could be improved by vinylene carbonate (VC) participating in forming a protective interfacial chemistry on soft carbon. In addition, the effect of P-doping on exothermic thermal reactions of lithiated soft carbon with electrolyte solution is discussed on the basis of differential scanning calorimetry (DSC) results.

• 한국전기화학회:학술대회논문집
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• 2001.04a
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• pp.39-39
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• 2001

• 한국전기화학회:학술대회논문집
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• 2003.04a
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• pp.24-24
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• 2003

• Journal of Electrochemical Science and Technology
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• v.8 no.4
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• pp.338-343
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• 2017

Activated carbon has lower electrical conductivity and reliability than other carbonaceous materials because of the oxygen functional groups that form during the activation process. This problem can be overcome by doping the material with heteroatoms to reduce the number of oxygen functional groups. In the present study, N, F co-doped activated carbon (AC-NF) was successfully prepared by a microwave-assisted hydrothermal method, utilizing commercial activated carbon (AC-R) as the precursor and ammonium tetrafluoroborate as the single source for the co-doping of N and F. AC-NF showed improved electrical conductivity ($3.8\;S\;cm^{-1}$) with N and F contents of 0.6 and 0.1 at%, respectively. The introduction of N and F improved the performance of the pertinent supercapacitor: AC-NF exhibited an improved rate capability at current densities of $0.5-50mA\;cm^{-2}$. The rate capability was higher compared to that of raw activated carbon because N and F codoping increased the electrical conductivity of AC-NF. The developed method for the co-doping of N and F using a single source is cost-effective and yields AC-NF with excellent electrochemical properties; thus, it has promising applications in the commercialization of energy storage devices.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.199-205
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• 2015

We investigated the effects of the thickness and doping concentration in p- and n-type poly-Si layers on the performance of a solar cell based on a carbon fiber in order to improve the energy conversion efficiency of the cell. The short-circuit current density and open-circuit voltage of the carbon fiber-based solar cell were significantly influenced by the thickness and doping concentration in the p- and n-type poly-Si layers. The solar cell efficiency was successfully enhanced to ~10.5%.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.763-769
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• 2012

We investigated the width (N) dependence on the magnetization of N-ZSiC NR with electron and hole doping on the basis of systematic DFT calculations. The critical values of the upper and down critical concentration to give the maximum and zero magnetic moment at edge Si/C atoms by electron/hole doping ($x_{up,e}$, $x_{down,e}$, $x_{up,h}$, and $x_{down,h}$) depend on the width of N-ZSiC NR. Moreover, due to $x_{up,e}\;{\neq}\;x_{up,h}$ and $x_{down,e}\;{\neq}\;x_{down,h}$, the electron and hole doping effect are asymmetry, i.e, the critical electron doping value ($x_{down,e}$) is smaller than the critical hole doping value ($x_{down,h}$) and is almost independent of the width of NZSiC NR though the other critical values of the electron and hole doping that influence the magnetization of N-ZSiC NR depend on the width. It was also found that at $x_{down,e}$ or $x_{down,h}$ doping, the N-ZSiC NR turns into unusual non-magnetic metallic state. The magnetic behavior was discussed based on the band structures and projected density of states (PDOS) under the effect of electron/hole doping.

• Elastomers and Composites
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• v.57 no.1
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• pp.9-12
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• 2022

Herein, a facile approach for the development of effective and low-cost carbon precursors from acrylonitrile-butadiene-styrene (ABS) rubber is reported. ABS rubber with a negligible char yield can be converted into an excellent carbon precursor with approximately 54% char yield under a nitrogen atmosphere at 800℃ by simple iodine doping and subsequent heating at 110℃ under an inert atmosphere. The enhanced char yield is attributed to the improved intermolecular interactions between the ABS chains caused by the formation of covalent bonds between the butadiene segments, along with the newly developed charge-charge interactions and other indiscriminate radical-radical couplings. The charges and radicals involved in these interactions are also generated by iodine doping. We believe that this study will be useful for the development of low-cost carbon precursors.