• 제목/요약/키워드: advanced nanocomposites

검색결과 140건 처리시간 0.025초

Synthesis and Characterization of CdSe/graphene Nanocomposites and their Catalytic Reusability Studies under Visible Light Radiation

  • Ali, Asghar;Oh, Won-Chun
    • 한국세라믹학회지
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    • 제52권6호
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    • pp.502-507
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    • 2015
  • We examined the photo catalytic activity and catalytic recyclability of CdSe/graphene nanocomposites fabricated via modified hydrothermal technique. The prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), transmission electron microscopy (TEM), Raman spectroscopic analysis, and X-ray photoelectron spectroscopy (XPS). The photocatalytic behavior was investigated through decomposition of RBB as a standard dye under visible light radiation. Our results indicate that there is significant potential for graphene based semiconductor hybrids materials to be used as photocatalysts under visible light irradiation for the degradation of organic dyes from industry effluents.

Photocatalytic Performance of CoS2-Graphene-TiO2 Ternary Composites for Reactive Black B (RBB) Degradation

  • Ali, Asghar;Oh, Won-Chun
    • 한국세라믹학회지
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    • 제54권4호
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    • pp.308-313
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    • 2017
  • In this study we examined the photo-degradation efficiency of $CoS_2-G-TiO_2$ nanocomposites under visible light irritation using Reactive Black B (RBB) as standard dye, $CoS_2-G-TiO_2$ nanocomposites synthesized by facial microwave assist technique, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopic analysis. Our results show the efficiency of the $CoS_2-G-TiO_2$ ternary nanocomposite is better than $CoS_2-G$ and $TiO_2-G$ nanocomposite. The degradation efficiency of $CoS_2-G-TiO_2$ nanocomposite was found approximately 89% of Reactive Black B (RBB) degraded after 180 min. Our results will open new way for the development of a new ternary nanocomposite photocatalytic application.

Electrical and Thermal Properties of Poly(p-phenylene sulfide) Reduced Graphite Oxide Nanocomposites

  • Chae, Byung-Jae;Kim, Do Hwan;Jeong, In-Soo;Hahn, Jae Ryang;Ku, Bon-Cheol
    • Carbon letters
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    • 제13권4호
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    • pp.221-225
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    • 2012
  • Graphite oxide (GO) was produced using the modified Hummer's method. Poly(p-phenylene sulfide) (PPS)/reduced graphite oxide (RGO) composites were prepared by in situ polymerization method. The electrical conductivity of the PPS/RGO composites was no more than 82 S/m. It was found that as GO content increased in the PPS/RGO composites, the crystallization temperature and electrical conductivity of the composites increased and the percolation threshold value was at 5-8 wt% of GO content.

Ultrasonic Synthesis of CoSe2-Graphene-TiO2 Ternary Composites for High Photocatalytic Degradation Performance

  • Ali, Asghar;Oh, Won-Chun
    • 한국세라믹학회지
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    • 제54권3호
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    • pp.205-210
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    • 2017
  • In this study, we examined the photo-degradation efficiency of $CoSe_2$-Graphene-$TiO_2$ ($CoSe_2-G-TiO_2$) nanocomposites under visible light irradiation using rhodamine B (RhB) as standard dye. $CoSe_2-G-TiO_2$ nanocomposites were synthesized by ultrasonication and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopic analysis and UV-Vis absorbance spectra analysis. Our results show that the $CoSe_2-G-TiO_2$ nanocomposite exhibited significant photo degradation efficiency compared to pure $TiO_2$ and $CoSe_2-G$, approximately 85.2% of the rhodamine (Rh B) degraded after 2.5 h. It is concluded that the $CoSe_2-G-TiO_2$ nanocomposite is a promising candidate for use in dye pollutants.

Modeling of CNTs and CNT-Matrix Interfaces in Continuum-Based Simulations for Composite Design

  • Lee, Sang-Hun;Shin, Kee-Sam;Lee, Woong
    • 한국재료학회지
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    • 제20권9호
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    • pp.478-482
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    • 2010
  • A series of molecular dynamic (MD), finite element (FE) and ab initio simulations are carried out to establish suitable modeling schemes for the continuum-based analysis of aluminum matrix nanocomposites reinforced with carbon nanotubes (CNTs). From a comparison of the MD with FE models and inferences based on bond structures and electron distributions, we propose that the effective thickness of a CNT wall for its continuum representation should be related to the graphitic inter-planar spacing of 3.4${\AA}$. We also show that shell element representation of a CNT structure in the FE models properly simulated the carbon-carbon covalent bonding and long-range interactions in terms of the load-displacement behaviors. Estimation of the effective interfacial elastic properties by ab initio simulations showed that the in-plane interfacial bond strength is negligibly weaker than the normal counterpart due to the nature of the weak secondary bonding at the CNT-Al interface. Therefore, we suggest that a third-phase solid element representation of the CNT-Al interface in nanocomposites is not physically meaningful and that spring or bar element representation of the weak interfacial bonding would be more appropriate as in the cases of polymer matrix counterparts. The possibility of treating the interface as a simply contacted phase boundary is also discussed.

방열소재 응용을 위한 알루미나 분말 표면 위 탄소나노튜브의 직접 성장 거동 고찰 (Investigation of direct growth behavior of carbon nanotubes on alumina powders to use as heat dissipation materials)

  • 이종환;한현호;정구환
    • 한국표면공학회지
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    • 제56권1호
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    • pp.55-61
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    • 2023
  • As a preliminary study to produce functional nanocomposites in a heat dissipation device, we performed the direct synthesis of carbon nanotubes (CNTs) on the surface of alumina (Al2O3) powders. A thermal chemical vapor deposition (TCVD) system was used to grow CNTs directly on the Al2O3 surface. In order to investigate the growth behavior of CNTs, we varied both furnace temperature of the TCVD ranging from 700 to 850 ℃ and concentration of the ferritin-dissolved DI solution from 0.1 to 2.0 mg/mL. From the previous results, the gas composition and duration time for CNT growth were fixed as C2H4 : H2 = 30 : 500 (vol. %) and 10 min, respectively. Based on the analysis results, the optimized growth temperature and ferritin concentration were found to be 825 ℃ and 0.5 mg/mL, respectively. The obtained results could be adopted to achieve mass production of nanocomposites with heat dissipation functionality.