http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
A review: controlled synthesis of vertically aligned carbon nanotubes
Myung-Gwan Hahm,Daniel P. Hashim,Robert Vajtai,Pulickel M. Ajayan 한국탄소학회 2011 Carbon Letters Vol.12 No.4
Carbon nanotubes (CNTs) have developed into one of the most competitively researched nano-materials of this decade because of their structural uniqueness and excellent physical properties such as nanoscale one dimensionality, high aspect ratio, high mechanical strength, thermal conductivity and excellent electrical conductivity. Mass production and structure control of CNTs are key factors for a feasible CNT industry. Water and ethanol vapor enhance the catalytic activity for massive growth of vertically aligned CNTs. A shower system for gas flow improves the growth of vertically aligned single walled CNTs (SWCNTs) by controlling the gas flow direction. Delivery of gases from the top of the nanotubes enables direct and precise supply of carbon source and water vapor to the catalysts. High quality vertically aligned SWCNTs synthesized using plasma enhance the chemical vapor deposition technique on substrate with suitable metal catalyst particles. This review provides an introduction to the concept of the growth of vertically aligned SWCNTs and covers advanced topics on the controlled synthesis of vertically aligned SWCNTs.
Satish, Tejus,Balakrishnan, Kaushik,Gullapalli, Hemtej,Nagarajaiah, Satish,Vajtai, Robert,Ajayan, Pulickel M. Techno-Press 2017 Structural monitoring and maintenance Vol.4 No.2
In this paper, we present a strain-sensitive composite skin-like film made up of piezoresistive zinc oxide (ZnO) nanorods embedded in a flexible poly(dimethylsiloxane) substrate, with added reduced graphene oxide (rGO) to facilitate connections between the nanorod clusters and increase strain sensitivity. Preparation of the composite is described in detail. Cyclic strain sensing tests are conducted. Experiments indicate that the resulting ZnO-PDMS/rGO composite film is strain-sensitive and thus capable of sensing cycling strain accurately. As such, it has the potential to be molded on to a structure (civil, mechanical, aerospace, or biological) in order to provide a strain sensing skin.
Functionalized Multilayered Graphene Platform for Urea Sensor
Srivastava, Rajesh K.,Srivastava, Saurabh,Narayanan, Tharangattu N.,Mahlotra, Bansi D.,Vajtai, Robert,Ajayan, Pulickel M.,Srivastava, Anchal American Chemical Society 2012 ACS NANO Vol.6 No.1
<P>Multilayered graphene (MLG) is an interesting material for electrochemical sensing and biosensing because of its very large 2D electrical conductivity and large surface area. We propose a less toxic, reproducible, and easy method for producing functionalized multilayer graphene from multiwalled carbon nanotubes (MWCNTs) in mass scale using only concentrated H<SUB>2</SUB>SO<SUB>4</SUB>/HNO<SUB>3</SUB>. Electron microscopy results show the MLG formation, whereas FTIR and XPS data suggest its carboxylic and hydroxyl-functionalized nature. We utilize this functionalized MLG for the fabrication of a novel amperometric urea biosensor. This biosensor shows linearity of 10–100 mg dL<SUP>–1</SUP>, sensitivity of 5.43 μA mg<SUP>–1</SUP> dL cm<SUP>–2</SUP>, lower detection limit of 3.9 mg dL<SUP>–1</SUP>, and response time of 10 s. Our results suggest that MLG is a promising material for electrochemical biosensing applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-1/nn203210s/production/images/medium/nn-2011-03210s_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn203210s'>ACS Electronic Supporting Info</A></P>
In Situ Synthesis of ThermochemicallyReduced Graphene Oxide Conducting Nanocomposites
Park, Ok-Kyung,Hahm, Myung Gwan,Lee, Sungho,Joh, Han-Ik,Na, Seok-In,Vajtai, Robert,Lee, Joong Hee,Ku, Bon-Cheol,Ajayan, Pulickel M. American ChemicalSociety 2012 NANO LETTERS Vol.12 No.4
<P>Highly conductive reduced graphene oxide (GO) polymer nano composites are synthesized by a well-organized in situ thermochemical synthesis technique. The surface functionalization of GO was carried out with aryl diazonium salt including 4-iodoaniline to form phenyl functionalized GO (I-Ph-GO). The thermochemically developed reduced, GO (R-I-Ph-GO) has five times higher electrical conductivity (42 000 S/m) than typical reduced GO (R-GO). We also demonstrate a R-I-Ph-GO/polyimide (PI) composites having more than 10(4) times higher conductivity (similar to 1 S/m) compared to a R-GO/PI composites. The electrical resistances of PI composites with R-I-Ph-GO were dramatically dropped under similar to 3% tensile strain. The R-I-Ph-GO/PI composites with electrically sensitive response caused by mechanical strain are expected to have broad implications for nanoelectromechanical systems.</P>
Ultrathin Planar Graphene Supercapacitors
Yoo, Jung Joon,Balakrishnan, Kaushik,Huang, Jingsong,Meunier, Vincent,Sumpter, Bobby G.,Srivastava, Anchal,Conway, Michelle,Mohana Reddy, Arava Leela,Yu, Jin,Vajtai, Robert,Ajayan, Pulickel M. American Chemical Society 2011 Nano letters Vol.11 No.4
<P>With the advent of atomically thin and flat layers of conducting materials such as graphene, new designs for thin film energy storage devices with good performance have become possible. Here, we report an “in-plane” fabrication approach for ultrathin supercapacitors based on electrodes comprised of pristine graphene and multilayer reduced graphene oxide. The in-plane design is straightforward to implement and exploits efficiently the surface of each graphene layer for energy storage. The open architecture and the effect of graphene edges enable even the thinnest of devices, made from as grown 1−2 graphene layers, to reach specific capacities up to 80 μFcm<SUP>−2</SUP>, while much higher (394 μFcm<SUP>−2</SUP>) specific capacities are observed multilayer reduced graphene oxide electrodes. The performances of devices with pristine as well as thicker graphene-based structures are examined using a combination of experiments and model calculations. The demonstrated all solid-state supercapacitors provide a prototype for a broad range of thin-film based energy storage devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2011/nalefd.2011.11.issue-4/nl200225j/production/images/medium/nl-2011-00225j_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl200225j'>ACS Electronic Supporting Info</A></P>
Carbon Nanotube Core Graphitic Shell Hybrid Fibers
Hahm, Myung Gwan,Lee, Jae-Hwang,Hart, Amelia H. C.,Song, Sung Moo,Nam, Jaewook,Jung, Hyun Young,Hashim, Daniel Paul,Li, Bo,Narayanan, Tharangattu N.,Park, Chi-Dong,Zhao, Yao,Vajtai, Robert,Kim, Yoong American Chemical Society 2013 ACS NANO Vol.7 No.12
<P>A carbon nanotube yarn core graphitic shell hybrid fiber was fabricated <I>via</I> facile heat treatment of epoxy-based negative photoresist (SU-8) on carbon nanotube yarn. The effective encapsulation of carbon nanotube yarn in carbon fiber and a glassy carbon outer shell determines their physical properties. The higher electrical conductivity (than carbon fiber) of the carbon nanotube yarn overcomes the drawbacks of carbon fiber/glassy carbon, and the better properties (than carbon nanotubes) of the carbon fiber/glassy carbon make up for the lower thermal and mechanical properties of the carbon nanotube yarn <I>via</I> synergistic hybridization without any chemical doping and additional processes.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-12/nn4045276/production/images/medium/nn-2013-045276_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn4045276'>ACS Electronic Supporting Info</A></P>