Browsing by Author "Polychronopoulou, K."

Now showing items 1-20 of 21

    • Article  

      Adaptive VN/Ag nanocomposite coatings with lubricious behavior from 25 to 1000 °c 

      Aouadi, S. M.; Singh, D. P.; Stone, D. S.; Polychronopoulou, K.; Nahif, F.; Rebholz, Claus; Muratore, C.; Voevodin, A. A. (2010)
      A two-phase nanocomposite coating that consists of inclusions of silver in a vanadium nitride matrix (VN/Ag) was investigated as a potential adaptive coating with a reduced friction coefficient from 25 to 1000 °C. This ...
    • Article  

      Deposition and nanotribological characterization of Sub-100-nm thick protective Ti-based coatings for miniature applications 

      Polychronopoulou, K.; Lee, J.; Tsotsos, C.; Demas, N. G.; Meschewski, R. L.; Rebholz, Claus; Polycarpou, A. A. (2011)
      Ti-based protective thin films with thicknesses below 100 nm, intended for miniature applications were deposited using physical vapor deposition magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy, ...
    • Conference Object  

      Effect of Cu content on the tribological performance of Cr-N coatings at high temperatures (840°C) 

      Polychronopoulou, K.; Rebholz, Claus; Demas, N. G.; Polycarpou, A. A.; Gibson, P. N. (Affiliation: Department of Mechanical and Manufacturing Eng., University of Cyprus, Nicosia, CyprusAffiliation: Department of Mechanical Science and Eng., University of Illinois at Urbana-Champaign, Urbana, IL, United StatesAffiliation: Institute for Health and Consumer Protection, Joint Res. Centre of the European Commission, Ispra (VA), ItalyCorrespondence Address: Polychronopoulou, K.Department of Mechanical and Manufacturing Eng., University of Cyprus, Nicosia, Cyprus, 2010)
      Cr-N and Cu-Cr-N coatings with Cu content between 3-65 at.%, Cu/Cr ratios in the 0.04-4.5 range and 21-27 at.% N, synthesized by twin e-beam Physical Vapor Deposition (EBPVD) at 450°C, were investigated. Using X-ray ...
    • Article  

      Few-step synthesis, thermal purification and structural characterization of porous boron nitride nanoplatelets 

      Kostoglou, N.; Lukovic, J.; Babic, B.; Matovic, B.; Photiou, D.; Constantinides, G.; Polychronopoulou, K.; Ryzhkov, V.; Grossmann, B.; Mitterer, C.; Rebholz, Claus (2016)
      Hexagonal boron nitride (h-BN) nanoplatelets with 99 wt.% purity, 900 to 2000 nm particle width, 30 to 90 nm particle thickness, 213 m2/g specific surface area (SSA), 66% micropore SSA and 0.85 nm average pore size were ...
    • Article  

      Growth and characterization of ceria thin films and Ce-doped γ - Al 2 O 3 nanowires using sol-gel techniques 

      Gravani, S.; Polychronopoulou, K.; Stolojan, V.; Cui, Q.; Gibson, P. N.; Hinder, S. J.; Gu, Z.; Doumanidis, C. C.; Baker, M. A.; Rebholz, Claus (2010)
      γ - Al 2 O 3 is a well known catalyst support. The addition of Ce to γ - Al 2 O 3 is known to beneficially retard the phase transformation of γ - Al 2 O 3 to α - Al 2 O 3 and stabilize the γ-pore structure. In this ...
    • Article  

      Mechanical and high pressure tribological properties of nanocrystalline Ti(N,C) and amorphous C:H nanocomposite coatings 

      Tsotsos, C.; Polychronopoulou, K.; Demas, N. G.; Constantinides, G.; Gravani, S.; Böbel, K.; Baker, M. A.; Polycarpou, A. A.; Rebholz, Claus (2010)
      This paper reports on the mechanical and high pressure tribological properties of nanocrystalline (nc-) Ti(N,C)/amorphous (a-) C:H deposited, using low temperature (∼200°C) DC reactive magnetron sputtering. The mechanical ...
    • Conference Object  

      Microstructure, mechanical and tribological properties of reactive magnetron sputtered titanium carbide coatings 

      Polychronopoulou, K.; Rebholz, Claus; Theodorou, L.; Böbel, K.; Demas, N. G.; Polycarpou, A. A. (Affiliation: Dept. of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, CyprusAffiliation: Dept. PA-ATM01/SGP21, Engineering Process Technology, Robert Bosch GmbH, Postfach 300220, 70442 Stuttgart, GermanyAffiliation: Dept. of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United StatesCorrespondence Address: Polycarpou, A. A.Dept. PA-ATM01/SGP21, Engineering Process Technology, Robert Bosch GmbH, Postfach 300220, 70442 Stuttgart, Germanyemail: polycarp@uiuc.edu, 2008)
      This study describes the correlation between the microstructure, mechanical and tribological properties of Ti 1-xCx coatings (with x being in the range of 0-0.5), deposited by reactive magnetron sputtering from a Ti target ...
    • Article  

      Nanoporous activated carbon cloth as a versatile material for hydrogen adsorption, selective gas separation and electrochemical energy storage 

      Kostoglou, N.; Koczwara, C.; Prehal, C.; Terziyska, V.; Babic, B.; Matovic, B.; Constantinides, G.; Tampaxis, C.; Charalambopoulou, Georgia; Steriotis, T.; Hinder, S.; Baker, M. A.; Polychronopoulou, K.; Doumanidis, C. C.; Paris, O.; Mitterer, C.; Rebholz, Claus (2017)
      The efficient storage of energy combined with a minimum carbon footprint is still considered one of the major challenges towards the transition to a progressive, sustainable and environmental friendly society on a global ...
    • Article  

      Nanostructure, mechanical and tribological properties of reactive magnetron sputtered TiCx coatings 

      Polychronopoulou, K.; Rebholz, Claus; Baker, M. A.; Theodorou, L.; Demas, N. G.; Hinder, S. J.; Polycarpou, A. A.; Doumanidis, C. C.; Böbel, K. (2008)
      This study describes the correlation between microstructure, mechanical and tribological properties of TiCx coatings (with x being in the range of 0–1.4), deposited by reactive magnetron sputtering from a Ti target in ...
    • Article  

      Nanostructure, mechanical and tribological properties of reactive magnetron sputtered TiCx coatings 

      Polychronopoulou, K.; Rebholz, Claus; Baker, M. A.; Theodorou, L.; Demas, N. G.; Hinder, S. J.; Polycarpou, A. A.; Doumanidis, C. C.; Böbel, K. (2008)
      This study describes the correlation between microstructure, mechanical and tribological properties of TiCx coatings (with x being in the range of 0-1.4), deposited by reactive magnetron sputtering from a Ti target in ...
    • Article  

      The nanostructure, wear and corrosion performance of arc-evaporated CrBxNy nanocomposite coatings 

      Polychronopoulou, K.; Baker, M. A.; Rebholz, Claus; Neidhardt, J.; O'Sullivan, M.; Reiter, A. E.; Kanakis, K.; Leyland, A.; Matthews, A.; Mitterer, C. (2009)
      The composition, nanostructure, tribological and corrosion behaviour of reactive arc evaporated CrBxNy coatings have been studied and compared to CrN. The CrBxNy coatings were deposited on a commercial Oerlikon Balzers RCS ...
    • Article  

      Novel CeO2-based screen-printed potentiometric electrodes for pH monitoring 

      Betelu, S.; Polychronopoulou, K.; Rebholz, Claus; Ignatiadis, I. (2011)
      Nuclear waste repositories are being installed in deep excavated rock formations in some places in Europe to isolate and store radioactive waste. In France, the Callovo-Oxfordian formation (COx) is a possible candidate for ...
    • Article  

      Room temperature synthesis and high temperature frictional study of silver vanadate nanorods 

      Singh, D. P.; Polychronopoulou, K.; Rebholz, Claus; Aouadi, S. M. (2010)
      We report the room temperature (RT) synthesis of silver vanadate nanorods (consisting of mainly β-AgVO3) by a simple wet chemical route and their frictional study at high temperatures (HT). The sudden mixing of ammonium ...
    • Article  

      Solvothermal synthesis, nanostructural characterization and gas cryo-adsorption studies in a metal–organic framework (IRMOF-1) material 

      Tzitzios, V.; Kostoglou, N.; Giannouri, M.; Basina, G.; Tampaxis, C.; Charalambopoulou, Georgia; Steriotis, T.; Polychronopoulou, K.; Doumanidis, C. C.; Mitterer, C.; Rebholz, Claus (2017)
      A nanoporous metal–organic framework material, exhibiting an IRMOF-1 type crystalline structure, was prepared by following a direct solvothermal synthesis approach, using zinc nitrate and terephthalic acid as precursors ...
    • Article  

      Structure and mechanical properties of low temperature magnetron sputtered nanocrystalline (nc-)Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings 

      Tsotsos, C.; Baker, M. A.; Polychronopoulou, K.; Gibson, P. N.; Giannakopoulos, K.; Polycarpou, A. A.; Böbel, K.; Rebholz, Claus (2010)
      This paper reports on the structure and mechanical properties of 2μm thick nanocomposite (nc-) Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings deposited on 100Cr6 steel substrates, using low temperature ( 200°C) DC ...
    • Article  

      Synthesis and characterization of Cr-B-N coatings deposited by reactive arc evaporation 

      Polychronopoulou, K.; Neidhardt, J.; Rebholz, Claus; Baker, M. A.; O'Sullivan, M.; Reiter, A. E.; Gunnaes, A. E.; Giannakopoulos, K.; Mitterer, C. (2008)
      Nanocomposite Cr-B-N coatings were deposited from CrB0.2 compound targets by reactive arc evaporation using an Ar/N2 discharge at 500 °C and -20 V substrate bias. Elastic recoil detection (ERDA), x-ray photoelectron ...
    • Article  

      Synthesis of nanoporous graphene oxide adsorbents by freeze-drying or microwave radiation: Characterization and hydrogen storage properties 

      Kostoglou, N.; Tzitzios, V.; Kontos, A. G.; Giannakopoulos, K.; Tampaxis, C.; Papavasiliou, A.; Charalambopoulou, Georgia; Steriotis, T.; Li, Y.; Liao, K.; Polychronopoulou, K.; Mitterer, C.; Rebholz, Claus (2015)
      In the present work, we synthesized and systematically characterized two novel graphene-based nanomaterials, a chemically reduced graphene oxide (GO) sponge and a microwave-exfoliated GO. Textural properties were determined ...
    • Article  

      Textured VN coatings with Ag3VO4 solid lubricant reservoirs 

      Luster, B.; Stone, D.; Singh, D. P.; Baben, M. to; Schneider, J. M.; Polychronopoulou, K.; Rebholz, Claus; Kohli, P.; Aouadi, S. M. (2011)
      Silver oxovanadate powders were produced using a low temperature hydrothermal synthesis method. X-ray diffraction (XRD) and Raman microscopy revealed the formation of the α-Ag3VO4 phase, and differential scanning calorimetry ...
    • Article  

      Thermal and chemical stability of hexagonal boron nitride (h-BN) nanoplatelets 

      Kostoglou, N.; Polychronopoulou, K.; Rebholz, Claus (2015)
      High-temperature properties of boron nitride platelets (200-800 nm in width and 30-50 nm in thickness) were systematically evaluated through thermogravimetric analysis (TGA) in combination with differential scanning ...
    • Conference Object  

      Tribological behavior of CrN and Al-Cr-N coatings 

      Demas, N. G.; Polycarpou, A. A.; Polychronopoulou, K.; Rebholz, Claus (Affiliation: Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United StatesAffiliation: Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, CyprusCorrespondence Address: Demas, N. G.Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States, 2009)
      The tribological behavior of CrN and Al-Cr-N coatings prepared by twin electron-beam evaporation at 450°C was investigated. The composition, structure, mechanical and tribological properties of the coatings were determined ...