• Title, Summary, Keyword: carbon nanomaterials

Search Result 139, Processing Time 0.039 seconds

Carbon nanomaterials in organic photovoltaic cells

  • Kim, Tae-Hoon;Yang, Seung-Jae;Park, Chong-Rae
    • Carbon letters
    • /
    • v.12 no.4
    • /
    • pp.194-206
    • /
    • 2011
  • Carbon nanomaterials in organic photovoltaic (OPV) cells have attracted a great deal of interest for the development of high-efficiency, flexible, and low-cost solar cells. Due to the complicated structure of OPV devices, the electrical properties and dispersion behavior of the carbon nanomaterials should be controlled carefully in order for them to be used as materials in OPV devices. In this paper, a fundamental theory of the electrical properties and dispersion behavior of carbon nanomaterials is reviewed. Based on this review, a state-of-the-art OPV device composed of carbon nanomaterials, along with issues related to such devices, are discussed.

Role of Metal Catalyst and Substrate Site for the Growth of Carbon Nanomaterials

  • Manocha, L.M.;Valand, Jignesh;Manocha, S.
    • Carbon letters
    • /
    • v.6 no.2
    • /
    • pp.79-85
    • /
    • 2005
  • The work reported in this paper relates to preparation and characterization of carbon nanomaterials by CVD method on different substrates by decomposition of certain hydrocarbons at 550-$800^{\circ}C$ using a horizontal quartz tube reactor. Monometallic and bimetallic catalyst system of iron and nickel were used for the preparation of different carbon nanomaterials. The influence of various parameters such as substrate/catalyst preparation parameters, the nature of substrate, catalyst concentration, reaction time and temperature on the growth, yield and alignment of carbon nanotubes has been studied. The characterization of carbon nanomaterials has been carried out using SEM, TEM and TGA. The carbon nanomaterials developed were vertically aligned on a large area of flat quartz substrate.

  • PDF

Mobility of Carbon Nanomaterials in Soil Media (토양 매질체에서 탄소나노물질의 이동성)

  • Yi, In-Geol;Kang, Jin-Kyu;Kim, Song-Bae;Kim, Hyunjung;Han, Yosep;Eom, Ig-Chun;Jo, Eunhye;Park, Sun-Young
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.36 no.8
    • /
    • pp.588-595
    • /
    • 2014
  • Carbon nanomaterials such as fullerene, carbon nanotube and graphene are representative nanomaterials and widely used in various fields. Carbon nanomaterials can be exposed to environments during their production, usage and disposal, spreading to different systems and posing a great threat to various ecological receptors. Researches are conducted in order to determine the possibility of groundwater exposure to carbon nanomaterials due to their release and passage through soils. If soils can play a significant role in limiting the transport of carbon nanomaterials, the possibility of groundwater exposure to carbon nanomaterials can be reduced greatly. This review paper presented the research works performed for the mobility of carbon nanomaterials in soil media. Also, the paper provided the factors affecting the transport of carbon nanomaterials in soil media along with the DLVO theory/colloid filtration theory/transport model, which are used to describe the transport of carbon nanomaterials in soil media. Recently, production of carbon nanomaterials and their commercial and environmental applications increase rapidly in Korea. Therefore, researches regarding the fate and transport of domestic carbon nanomaterials in soil environments should be performed in various environmental conditions.

Sensing performances of Semiconducting Carbon Nanomaterials based Gas Sensors Operating at Room Temperature (반도체 탄소 나노재료 기반 상온 동작용 가스센서)

  • Choi, Sun-Woo
    • Ceramist
    • /
    • v.22 no.1
    • /
    • pp.96-106
    • /
    • 2019
  • Semiconducting carbon-based nanomaterials including single-walled carbon nanotubes(SWCNTs), multi-walled CNT(MWCNTs), graphene(GR), graphene oxide(GO), and reduced graphene oxide(RGO), are very promising sensing materials due to their large surface area, high conductivity, and ability to operate at room temperature. Despite of these advantages, the semiconducting carbon-based nanomaterials intrinsically possess crucial disadvantages compared with semiconducting metal oxide nanomaterials, such as relatively low gas response, irreversible recovery, and poor selectivity. Therefore, in this paper, we introduce a variety of strategies to overcome these disadvantages and investigate principle parameters to improve gas sensing performances.

Molecular Dynamics of Carbon Nanotubes Deposited on a Silicon Surface via Collision: Temperature Dependence

  • Saha, Leton C.;Mian, Shabeer A.;Kim, Hyo-Jeong;Saha, Joyanta K.;Matin, Mohammad A.;Jang, Joon-Kyung
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.2
    • /
    • pp.515-518
    • /
    • 2011
  • We investigated how temperature influences the structural and energetic dynamics of carbon nanotubes (CNTs) undergoing a high-speed impact with a Si (110) surface. By performing molecular dynamics simulations in the temperature range of 100 - 300 K, we found that a low temperature CNT ends up with a higher vibrational energy after collision than a high temperature CNT. The vibrational temperature of CNT increases by increasing the surface temperature. Overall, the structural and energy relaxation of low temperature CNTs are faster than those of high temperature CNTs.

Physicochemical and Electrochemical Characteristics of Carbon Nanomaterials and Carbon Nanomaterial-Silicon Composites

  • Kim, Soo-Jin;Hyun, Yura;Lee, Chang-Seop
    • Journal of the Korean Chemical Society
    • /
    • v.60 no.5
    • /
    • pp.299-309
    • /
    • 2016
  • In this study, the physicochemical and electrochemical properties of carbon nanomaterials and synthesized nano-carbon/Si composites were studied. The nano-carbon/Si composites were ball-milled to a nano size and coated with pyrolytic carbon using Chemical Vapor Deposition (CVD). They were then finely mixed with respective nano-carbon materials. The physicochemical properties of samples were analyzed using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Raman spectroscopy, X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and surface area analyzer. The electrochemical characteristics were investigated using the galvanostatic charge-discharge and cyclic voltammetry (CV) measurements. Three-electrode cells were fabricated using the carbon nanomaterials and nano-carbon/Si composites as anode materials and LiPF6 and LiClO4 as electrolytes of Li secondary batteries. Reversibility using LiClO4 as an electrolyte was superior to that of LiPF6 as the electrolyte. The initial discharge capacities of nano-carbon/Si composites were increased compared to the initial discharge capacities of nano-carbon materials.

Effects of Morphologies of Carbon Nanomaterials on Conductivity of Composites Containing Copper/Carbon Nanomaterial Hybrid Fillers (탄소 나노 물질의 형상에 따른 구리/탄소나노물질 하이브리드 필러의 전도성 향상 거동 분석)

  • Lee, Yeonjoo;Hong, Sung-uk;Choi, Hyunjoo
    • Journal of Korean Powder Metallurgy Institute
    • /
    • v.25 no.5
    • /
    • pp.435-440
    • /
    • 2018
  • In the present study, we develop a conductive copper/carbon nanomaterial additive and investigate the effects of the morphologies of the carbon nanomaterials on the conductivities of composites containing the additive. The conductive additive is prepared by mechanically milling copper powder with carbon nanomaterials, namely, multi-walled carbon nanotubes (MWCNTs) and/or few-layer graphene (FLG). During the milling process, the carbon nanomaterials are partially embedded in the surfaces of the copper powder, such that electrically conductive pathways are formed when the powder is used in an epoxy-based composite. The conductivities of the composites increase with the volume of the carbon nanomaterial. For a constant volume of carbon nanomaterial, the FLG is observed to provide more conducting pathways than the MWCNTs, although the optimum conductivity is obtained when a mixture of FLG and MWCNTs is used.

Recent Application of the Various Nanomaterials and Nanocatalysts for the Heavy Metals' Removal from Wastewater

  • Khaligh, Nader Ghaffari;Johan, Mohd Rafie
    • Nano
    • /
    • v.13 no.9
    • /
    • pp.1830006.1-1830006.35
    • /
    • 2018
  • The pollution of water due to the release of heavy metals are particularly problematic and supplies of clean water have become a major problem worldwide. The heavy metal ions can cause toxicities and serious side effects toward human health; therefore, these metal ions should be removed from water and wastewater. A variety of strategies have been developed for efficient heavy metal removal from waters. Adsorption/ion exchange strategy play a great important role in removing heavy metal ions due to their advantages. Nanomaterials are excellent adsorbents and extensive studies have been performed to remove heavy metals from wastewater by developing and using various nanomaterials. Recent developments for the heavy metals removal by various nanomaterials, mainly including carbon-based nanomaterials, iron-based nanomaterials and photocatalytic nanomaterials in batch and flow systems are described in this review.

Molecular Dynamics Simulation Study on the Carbon NanotubeInteracting with a Polymer

  • Saha, Leton C.;Mian, Shabeer A.;Jang, Joon-Kyung
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.3
    • /
    • pp.893-896
    • /
    • 2012
  • Using molecular dynamics simulation method, we studied the carbon nanotube (CNT) non-covalently interacting with a polymer. As the polymer coiled around the CNT, the diameter of CNT deformed by more than 40% of its original value within 50 ps. By considering three different polymers, we conclude that the interaction between the CNT and polymer is governed by the number of repeating units in the polymer, not by the molecular weight of polymer.

Synthesis of Carbon Nanotubes and Nanofibers on a Substrate Coated with Metal Nitrates using an C2H4 Inverse Diffusion Flame (메탈나이트레이트가 도포된 기판과 C2H4 역확산화염을 이용한 탄소나노튜브 및 탄소나노섬유의 합성)

  • Lee, Gyo-Woo;Jurng, Jong-Soo;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.27 no.10
    • /
    • pp.1480-1488
    • /
    • 2003
  • Synthesis of carbon nanomaterials on a substrate coated with metal nitrates using an ethylene fueled inverse diffusion flame was illustrated. The effects of radial distance, residence time of the substrate, and hydrocarbon composition on the synthesis of carbon nanomaterials were investigated. The effects of catalyst metal particles were also studied using SUS304 substrates coated with Fe(NO$_3$)$_3$ (ferric nitrate, nonahydrate) and Ni(NO$_3$)$_2$(nickel nitrate, hexahydrate), and Cu substrate. Carbon nanomaterials, with diameters ranging from 30 - 70 nm, were observed on the substrate for both cases of using substrates only and using them with metal nitrates. In case of using the substrate with metal nitrates, the formation and growth of carbon nanomaterials were occurred in the lower temperature region than that of using the substrates only due to the easy activation of the metal particles coated on the surface of the substrates.