간행물
Carbon Letters KCI 등재 Carbon letters
- 발행기관 한국탄소학회
- 자료유형 학술지
- 간기 연7회
- ISSN 1976-4251 (Print)2233-4998 (Online)
- 수록기간 2000 ~ 2025
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 530DDC 620
권호리스트/논문검색
Vol.35 No.1 (2025년 2월) 26건
21.
2025.02
구독 인증기관 무료, 개인회원 유료
Segregated composites, where fillers are selectively placed at the matrix interface to form a segregated filler network, are attracting attention because they can provide excellent conductive properties at low filler content. In this study, the anisotropic enhancement in thermal conductivity of composites was discovered due to the unique structure of the segregated network. The segregated composites were produced using a typical mechanical mixing of matrix pellets and the internal structure was precisely analyzed using three-dimensional non-destructive analysis. The segregated composites slightly improved in the through-plane thermal conductivity, but the in-plane thermal conductivity increased rapidly, showing the anisotropic thermal conductivity. The maximum improvement in the in-plane thermal conductivity of the segregated composites increased by 112.5 (at 7 wt% graphene nanoplatelet) and 71.4% (at 10 wt% multi-walled carbon nanotube), respectively, compared to that of the random composites filled with the same amount of filler. On the other hand, the electrical conductivity of the segregated composites was isotropic due to the difference in the transport mechanisms of electrons and phonons. The anisotropic thermal conductivity developed by the segregated network was helpful in inducing effective heat dissipation of commercial smartphone logic boards.
4,000원
22.
2025.02
구독 인증기관 무료, 개인회원 유료
Young Nam Kim, Yebom Kim, Chetna Tewari, Hyunsung Jeong, Somi Yoon, Yong‑Seok Choi, Sungho Lee, Sung‑Kon Kim, Yong Chae Jung
In response to the urgent need for sustainable and environmentally friendly materials, this study focuses on enhancing the flame retardancy and mechanical properties of epoxy composites using eco-friendly, non-halogen flame-retardant hybrid fillers. These fillers are synthesized from tannic acid (TA) and upcycled carbon black derived from waste tires (WT-CB) via a mechano-fusion process. The resulting TA/WT-CB fillers exhibit a core–shell structure, with WT-CB uniformly coating the TA surface, significantly improving flame retardancy compared to TA alone. When incorporated into epoxy resin, the TA/WT-CB fillers not only enhance flame resistance but also improve the composite’s mechanical properties. Optimal performance was observed at a filler content of 5 wt.%, where the composite demonstrated superior flame retardancy and mechanical strength. This innovative approach not only addresses fire safety concerns but also promotes sustainability by utilizing upcycled waste materials, offering a promising solution for environmentally conscious flame-retardant technologies.
4,300원
23.
2025.02
구독 인증기관 무료, 개인회원 유료
The surface treatment processes of carbon fibers is very important, because of their significant impact on fiber handling, filament protection, and interfacial properties. In this study, the effects of two different sizing agents with different molecular weights, with or without a nonionic surfactant, on the performance of a melt-spun polyacrylonitrile-based carbon fiber and carbon fiber/epoxy interfacial adhesion are investigated. The focusing property and spread-ability of a low-molecularweight sizing agent with a surfactant show outstanding performances because of the high penetration between the fibers and high interfacial bonding with the fibers. In addition, wettability of the matrix (epoxy resin) of the low-molecular-weight sizing agent are superior to those of the high-molecular-weight sizing agent. Furthermore, the nonionic surfactant used as an assistant improves the sizing amount and wettability by forming micelles with the epoxy. The interfacial shear strength (IFSS) of the low-molecular-weight sizing agent with a surfactant is also superior to that of other sizing agents. The IFSS is closely related to the sizing amount of the coating on the carbon fiber surface and matrix wettability.
4,000원
24.
2025.02
구독 인증기관 무료, 개인회원 유료
This study explores the development and characterization of hard carbon anodes for sodium-ion batteries produced from waste coffee grounds, synthesized at both 1000 °C and 1500 °C. Importantly, this work highlights the potential of using biomass-derived hard carbons as sustainable and effective material for anode for sodium-ion batteries, contributing to the advancement of energy storage systems with increasing global demands for environmentally friendly and cost-effective technologies. The research focuses on the electrochemical performance of these hard carbons, examining how different carbonization temperatures impact their structural and electrochemical properties. Utilizing advanced analytical methods, the structural changes correlating with temperature increase were identified, including modifications in carbon atom arrangements, which significantly influence the electrochemical behaviors of the hard carbons. Our research specifically focuses on how the structural differences affect the division of capacity contribution from sloping region (above 0.1 V) and plateau regions (below 0.1 V). Electrochemical test results revealed that hard carbon with higher degree of order and reduced microstructural defects, demonstrated improved capacity values. At the same time, the highly ordered hard carbon exhibits drastic capacity loss upon increasing of current densities. The results from this study not only advance our understanding of hard carbons but also open pathways for the future exploration of hard carbons for additional improvements.
4,500원
25.
2025.02
구독 인증기관 무료, 개인회원 유료
Joon Young Kim, Chanmin Jo, Dae Jun Moon, Gyoung Hwa Jeong, Gnanaprakasam Janani, Seungryul Yoo, Dong Chan Seok, Seon Yeop Jung, Tae‑Hoon Kim, Ho‑Young Jung, Uk Sim
For the commercialization of bipolar plates, several properties must be considered together. Electrical conductivity, corrosion resistance, contact resistance, mechanical strength, and light weight are essential evaluation factors, with corrosion resistance and durability being significant for unitized regenerative fuel cells (URFCs), which must operate in electrolysis and fuel cell mode. However, improving both properties is challenging, since corrosion resistance is largely inversely proportional to conductivity. In this study, to improve both properties together, composites composed of Pb and Zn with excellent conductivity and corrosion resistance were prepared with graphite powder and formed as a coating layer on the surface of 304 stainless steel (SS304) and evaluated for electrical conductivity and corrosion resistance. Among the ZnPb/C composites prepared at various ratios, Zn8Pb2/C exhibited the lowest transmittance resistance of 1.566 Ω, and improved electrical conductivity and durability compared to bare SS304.
4,000원
26.
2025.02
구독 인증기관 무료, 개인회원 유료
Oxyfluorination treatment was used to enhance the electrochemical properties of SiOx/C-based lithium-ion battery anode materials by improving the dispersibility of multi-walled carbon nanotubes, which are conductive materials. The dispersibility, chemical, and morphological characteristics of the oxyfluorinated carbon nanotubes were confirmed through various analyses. In addition, the effect of oxyfluorination was analyzed by a lithium-ion battery performance test, and the discharge capacity and cycling stability were significantly improved. The introduction of oxygen functional groups onto the surface of the carbon nanotubes improved their dispersibility. The fluorine functional groups also acted as catalysts for the introduction of these oxygen functional groups onto the surface and improved the cycling stability by forming a LiF-based solid electrolyte interphase layer. The high discharge capacity and improved cycling stability of these lithium-ion batteries were attributed to the enhanced dispersibility of carbon nanotubes induced by oxyfluorination and the resulting enhancement of the 3D network in the anode material promoting the movement of lithium ions and electrons.
4,000원
1
2
