V
Viliam Vretenár
Researcher at Slovak University of Technology in Bratislava
Publications - 51
Citations - 699
Viliam Vretenár is an academic researcher from Slovak University of Technology in Bratislava. The author has contributed to research in topics: Carbon nanotube & Graphene. The author has an hindex of 12, co-authored 46 publications receiving 492 citations. Previous affiliations of Viliam Vretenár include Slovak Academy of Sciences.
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Diamond/carbon nanotube composites: Raman, FTIR and XPS spectroscopic studies
Marian Varga,Tibor Izak,Viliam Vretenár,Halyna Kozak,Jakub Holovsky,Anna Artemenko,Martin Hulman,Viera Skakalova,Dong Su Lee,Alexander Kromka +9 more
TL;DR: In this paper, a composite of single-wall carbon nanotubes (SWCNT) with diamond nanoparticles and a SWCNT paper coated with nanocrystalline diamond films is studied.
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Biomass waste-carbon/reduced graphene oxide composite electrodes for enhanced supercapacitors
L. Guardia,Loreto Suárez,Nausika Querejeta,Viliam Vretenár,Peter Kotrusz,Viera Skakalova,Teresa A. Centeno +6 more
TL;DR: In this article, a simple and effective alternative which optimizes electrodes based on low-cost carbons for high-performance supercapacitors is presented, which greatly improves the operation of microporous carbons easily produced by one-pot activation of grape seeds.
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Chemical Oxidation of Graphite: Evolution of the Structure and Properties
Viera Skakalova,Peter Kotrusz,Matej Jergel,Toma Susi,Andreas Mittelberger,Viliam Vretenár,Peter Siffalovic,Jani Kotakoski,Jannik C. Meyer,Martin Hulman +9 more
TL;DR: In this paper, a nonlinear behavior of oxygen uptake with time where two concentration plateaus were identified: Uptake reached 20 at % in the first 15 min, and after 1 h a second uptake started, reaching a highest oxygen concentration of >30 at % after 2 h of oxidation.
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Reduced graphite oxide in supercapacitor electrodes
TL;DR: It is shown that reduced graphite oxide offers a very interesting potential as promising supercapacitor electrodes, and that exfoliated from smaller particles (<75 μm) result more advantageous for the release of the stored electrical energy.
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Hot-Ball Method for Measuring Thermal Conductivity
TL;DR: In this article, the theory and performance of a sensor for measuring thermal conductivity in a hollow sphere in an infinite medium has been investigated, and the functionality of a set of hot balls has been tested and the calibration for a limited range of thermal conductivities was performed.