Mechanical Reinforcement of Electrospun Poly(Vinyl Alcohol) by a-FeOOH Nanowires
Anna Sutka, Martin Jarvekulg, Andris Sutka, Ivo Heinmaa, Uno Maeorg, Krisjanis Smits, Martin Timusk We report the mechanical performance of α-FeOOH nanowire reinforced poly(vinyl alcohol) (PVA) composite nanofiber mat, fabricated using straightforward aqueous processing methods. Goethite (α-FeOOH) nanocrystals have a high elastic modulus and –OH rich surface, ensuring strong interactions with hydrophilic polymers and effective reinforcement. […]
Unexpected Epitaxial Growth of a Few WS2 Layers on 1100 Facets of ZnO Nanowires
Boris Polyakov, Alexei Kuzmin, Krisjanis Smits, Janis Zideluns, Edgars Butanovs, Jelena Butikova, Sergei Vlassov, Sergei Piskunov, and Yuri F. Zhukovskii Core-shell nanowires is an interesting and perspective class of radially heterostructured nanomaterials where epitaxial growth of the shell can be realized even at significant core-shell lattice mismatch. In this study epitaxial hexagonally-shaped shell consisting of WS2 […]
Luminescent PEO Coatings on Aluminum
Aleksejs Zolotarjovs, Krisjanis Smits, Anete Krumina, DonatsMillers, and Larisa Grigorjeva Results show the possibilities of pore filling approach to modify alumina coatings with various materials in order to enhance coating optical (or other) properties and develop new functional materials; as well as demonstrate novel alumina phase transition detection approach. Luminescent PEO coatings were produced on aluminum surface using […]
Complex tribomechanical characterization of ZnO nanowires: nanomanipulations supported by FEM simulations
Sergei Vlassov, Boris Polyakov, Sven Oras, Mikk Vahtrus, Mikk Antsov, Andris Šutka Krisjanis Smits, Leonid M Dorogin and Rünno Lõhmus Abstract In the present work, we demonstrate a novel approach to nanotribological measurements based on the bending manipulation of hexagonal ZnO nanowires (NWs) in an adjustable halfsuspended configuration inside a scanning electron microscope. A pick-and-place […]
Europium(III)-doped A2Hf2O7 (A ¼ Y, Gd, Lu) nanoparticles: Influence of annealing temperature, europium(III) concentration and host cation on the luminescent properties
Jelena Papan , Dragana J. Jovanovic , Katarina Vukovic , Krisjanis Smits , Vesna ÐorCevic , Miroslav Dramicanin The detailed analyses of structure and luminescence of europium(III)-doped A2Hf2O7 (A ¼ Y, Gd, Lu) nanoparticles is presented. Samples were prepared by time and cost effective combustion method that utilize polyethylene glycol both as a chelating agent […]
Effect of Point Defects on Luminescence Characteristics of ZnO Ceramics
P. A. Rodnyi, K. A. Chernenko, A. Zolotarjovs, L. Grigorjeva, E. I. Gorokhova, and I. D. Venevtsev Abstract—Photo- and thermally stimulated luminescence of ZnO ceramics are produced by uniaxial hot pressing. The luminescence spectra of ceramics contain a wide band with a maximum at 500 nm, for which oxygen vacancies VO are responsible, and a narrow band […]
Ag sensitized TiO2 and NiFe2O4 three-component nanoheterostructures: synthesis, electronic structure and strongly enhanced visible light photocatalytic activity
A. Šutka, T. Käämbre, R. Pärna, N. Doebelin, M. Vanags, K. Smits and V. Kisand This study reports on the synthesis and characterisation of two- and three-component visible light active photocatalytic nanoparticle heterostructures, based on TiO2 and NiFe2O4 and sensitized with Ag. We observe that Ag content as small as 1 at.% in the TiO2/NiFe2O4 […]
Rare earth doped glass–ceramics containing NaLaF4 nanocrystals
E. Elsts , G. Krieke, U. Rogulis, K. Smits, A. Zolotarjovs, J. Jansons, A. Sarakovskis, K. Kundzins Oxyfluoride glasses 16Na2O–9NaF–5LaF3–7Al2O3–63SiO2 (mol%) activated with 3% terbium, dysprosium, praseodymium and neodymium fluorides have been prepared and studied by differential thermal analysis, cathodoluminescence, X-ray induced luminescence, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. We found […]