Carbon Letters Vol.16 No.4

1.

2015.12 구독 인증기관 무료, 개인회원 유료

Advances in liquid crystalline nano-carbon materials: preparation of nano-carbon based lyotropic liquid crystal and their fabrication of nano-carbon fibers with liquid crystalline spinning

Yong-Mun Choi, Jin Jung, Jun Yeon Hwang, Seung Min Kim, Hyeonsu Jeong, Bon-Cheol Ku, Munju Goh

Carbon Letters Vol.16 No.4 pp.223-232 한국탄소학회

This review presents current progress in the preparation methods of liquid crystalline nanocarbon materials and the liquid crystalline spinning method for producing nano-carbon fibers. In particular, we focus on the fabrication of liquid crystalline carbon nanotubes by spinning from superacids, and the continuous production of macroscopic fiber from liquid crystalline graphene oxide.

4,000원

2.

2015.12 구독 인증기관 무료, 개인회원 유료

Electrochemical synthesis of nanosized hydroxyapatite/graphene composite powder

Vesna Mišković-Stanković, Sanja Eraković, Ana Janković, Maja Vukašinović-Sekulić, Miodrag Mitrić, Young Chan Jung, Soo Jin Park, Kyong Yop Rhee

Carbon Letters Vol.16 No.4 pp.233-240 한국탄소학회

Electrochemical synthesis was employed to prepare a novel hydroxyapatite/graphene (HAP/ Gr) composite powder suitable for medical applications as a hard tissue implant (scaffold). The synthesis was performed in a homogeneous dispersion containing Na2H2EDTA·2H2O, NaH2PO4 and CaCl2 with a Ca/EDTA/PO4 3− concentration ratio of 0.25/0.25/0.15M, along with 0.01 wt% added graphene nanosheets, at a current density of 137 mA cm−2 and pH value of 9.0. The field emission scanning electron microscopy and transmission electron microscopy observations of the composite HAP/Gr powder indicated that nanosized hydroxyapatite particles were uniformly placed in the graphene overlay. Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction confirmed graphene incorporation in the HAP/Gr powder. The electrochemically prepared HAP/Gr composite powder exhibited slight antibacterial effect against the growth of the bacterial strain Staphylococcus aureus.

4,000원

3.

2015.12 구독 인증기관 무료, 개인회원 유료

Influence of laminated orientation on the mechanical and thermal characteristics of carbon-fiber reinforced plastics

Hee-Jae Shin, Lee-Ku Kwac, Min-Sang Lee, Hong-Gun Kim

Carbon Letters Vol.16 No.4 pp.241-246 한국탄소학회

Rapid industrial development in recent times has increased the demand for light-weight materials with high strength and structural integrity. In this context, carbon fiber-reinforced plastic (CFRP) composite materials are being extensively used. However, laminated CFRPs develop faults during impact because CFRPs are composed of mixed carbon fiber and epoxy. Moreover, their fracturing behavior is very complicated and difficult to interpret. In this paper, the effect of the direction of lamination in CFRP on the absorbed impact energy and impact strength were evaluated, including symmetric ply (0°/0°, –15°/+15°, –30°/+30°, –45°/+45°, and –90°/+90°) and asymmetric ply (0°/15°, 0°/30°, 0°/45°, and 0°/90°), through drop-weight impact tests. Further, the thermal properties of the specimens were measured using an infrared camera. Correlations between the absorbed impact energy, impact strength, and thermal properties as determined by the drop-weight impact tests were analyzed. These analyses revealed that the absorbed impact energy of the specimens with asymmetric laminated angles was greater than that of the specimens with symmetric laminated angles. In addition, the asymmetry ply absorbed more impact energy than the symmetric ply. Finally, the absorbed impact energy was inversely proportional to the thermal characteristics of the specimens.

4,000원

4.

2015.12 구독 인증기관 무료, 개인회원 유료

Photocatalytic performance of graphene/Ag/TiO2 hybrid nanocomposites

Jong-Ho Lee, In-Ki Kim, Donghwan Cho, Jeong-Il Youn, Young-Jig Kim, Han-Jun Oh

Carbon Letters Vol.16 No.4 pp.247-254 한국탄소학회

To improve photocatalytic efficiency, graphene/Ag/TiO2 nanotube catalyst was synthesized, and its surface characteristics and photocatalytic activity investigated. For deposition of Ag nanoparticles on the TiO2 nanotubes, a polymer compound containing CH3COOAg/poly(Llactide) was utilized, and the silver particles were precipitated by reducing the silver ions during the annealing process. Graphene deposition on the Ag/TiO2 nanotubes was achieved using an electrophoretic deposition process. Based on the dye degradation results, it was determined that the photocatalytic efficiency was significantly affected by deposition of silver particles and graphene on the TiO2 catalyst. Highly efficient destruction of the dye was obtained with the new graphene/Ag/TiO2 nanotube photocatalyst. This may be attributed to a synergistic effect of the graphene and Ag nanoparticles on the TiO2 nanotubes.

4,000원

5.

2015.12 구독 인증기관 무료, 개인회원 유료

Structural properties of reduced graphene oxides prepared using various reducing agents

Byung Soo Lee, Yangjin Lee, Jun Yeon Hwang, Young Chul Choi

Carbon Letters Vol.16 No.4 pp.255-259 한국탄소학회

4,000원

6.

2015.12 구독 인증기관 무료, 개인회원 유료

Catalytic activity and controllable deposition of platinum nanoparticles on ionic polymer-functionalized graphene as catalysts for direct methanol fuel cells

Jiyoung Park, Changyoon Song, Qizhong Sun, Yongju Jung, Seok Kim

Carbon Letters Vol.16 No.4 pp.260-264 한국탄소학회