Información del autor
Autor Piqueras de Noriega, Javier |
Documentos disponibles escritos por este autor (322)
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Urbieta Quiroga, Ana Irene ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | Amer Inst Physics | 2004-12-13Sintering CdSe powder under argon flow at temperatures in the range 800-900 degreesC produces the formation of needles on the sample surface. Bundles of parallel needles of a diameter of about 50 nm give rise to a domain-like appearance in the s[...]texto impreso
Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2005-02-15Sintering SnO_2 under argon flow at temperatures in the range of 1350-1500 degreesC causes the formation of wires, rods, and tubes on the sample surface. At high temperatures of the mentioned range, microwires with lengths of hundreds of microns[...]texto impreso
Sintering of ZnO pressed powder under Ar flow at temperatures between 1250 and 1300 degrees C leads to the formation of elongated microstructures and nanostructures, with different morphologies, on the sample surface. Rods and needles with cross[...]texto impreso
Nanorods of titanium oxide (TiO_2) were obtained by thermally activated growth process carried out on pellets of nanocrystalline powder with mixed anatase and rutile structures. The nanostuctured array consists of nanorods with length between 30[...]texto impreso
Hidalgo Alcalde, Pedro ; Méndez Martín, Bianchi ; Piqueras de Noriega, Javier | IOP publishing ltd | 2007-04-18High aspect ratio GeO_2 nano- and microwires have been grown by thermal treatment at 600 degrees C of compacted Ge powder under argon flow. The wires have cross-sectional dimensions from less than 100 nm to about 1 mu m, depending on the duratio[...]texto impreso
Bartolomé Vílchez, Javier ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | Amer Inst Physics | 2015-11-09The mechanical resonance behavior of as-grown In_2O_3 microrods has been studied in this work by in-situ scanning electron microscopy (SEM) electrically induced mechanical oscillations. Indium oxide microrods grown by a vapor–solid method are na[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier | American Institute of Physics | 1996-07-15Cathodoluminescence (CL) of YBa_2Cu_3O_(7-x) single crystals has been investigated in the scanning electron microscope, Some regions of the crystals, generally related to steps or other growth features, show enhanced CL Intensity. Spectra show t[...]texto impreso
Hidalgo Alcalde, Pedro ; Méndez Martín, Bianchi ; Piqueras de Noriega, Javier ; Dutta, P. S. | Materials Research Society | 1998Cathodoluminescence (CL) in the scanning electron microscope (SEM) has been used to investigate the effect of doping with an isoelectronic dopant, aluminum, on the native accepters and on the general structure of extended defects of gallium anti[...]texto impreso
Bazta, Otman ; Urbieta Quiroga, Ana Irene ; Trasobares, Susana ; Piqueras de Noriega, Javier ; Fernández Sánchez, Paloma ; Addou, Mohammed ; Calvino, Jose Juan ; Hungría, Ana Belén | MDPI | 2020-05Pure and Ce-modified ZnO nanosheet-like polycrystalline samples were successfully synthesized by a simple and fast microwave-based process and tested as photocatalytic materials in environmental remediation processes. In an attempt to clarify th[...]texto impreso
In-doped gallium oxide micro- and nanostructures: morphology, structure, and luminescence properties
López, Iñaki ; Utrilla, Antonio D. ; Nogales Díaz, Emilio ; Méndez Martín, Bianchi ; Piqueras de Noriega, Javier ; Peche, Andrea ; Ramirez Castellanos, J. ; González Calbet, José M. | Amer Chemical Soc | 2012-02-16The influence of indium doping on morphology, structural, and luminescence properties of gallium oxide micro- and nanostructures is reported. Indium-doped gallium oxide micro- and nanostructures have been grown by thermal oxidation of metallic g[...]texto impreso
Bartolomé Vílchez, Javier ; Hidalgo Alcalde, Pedro ; Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2014-04-21Electric field induced mechanical resonances of In2O3 microrods are studied by in-situ measurements in the chamber of a scanning electron microscope. Young's moduli of rods with different cross-sectional shapes are calculated from the resonance [...]texto impreso
Piqueras de Noriega, Javier ; Ortega Villafuerte, Yanicet ; Fernández Sánchez, Paloma ; Häußler, Dietrich ; Jäger, Wolfgang | IOP publishing ltd | 2013-10-02ZnO nanorods with Sn core regions grown by a thermal evaporation–deposition method from a mixture of SnO_2 and ZnS powders as precursors, are used to study the behaviour of liquid metal in the nanotubes' core regions and the formation of liquid [...]texto impreso
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Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Gregorati, Luca ; Piqueras de Noriega, Javier | American Chemical Soc. | 2010-03-04Mixtures of InN and SnO2 powders, with it weight ratio of 10:1, have been used as precursors for the thermal growth of arrow-shaped and other elongated micro- and nanostructures of indium-tin oxide (ITO) containing about 2.6 atom % of Sit. The t[...]texto impreso
Alemán, B. ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | Amer Inst Physics | 2009-07-06Indium-zinc-oxide (IZO) nanobelts have been grown by a thermal evaporation-deposition method with ZnO and In-2O_3 powders as precursors. The nanobelts have a superlattice structure that is explained by the formation of In-O and In/Zn-O layers, w[...]texto impreso
Bartolomé Vílchez, Javier ; Maestre Varea, David ; Amati, Mateo ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | Amer Chemical Soc | 2011-04-28Micropyramids of zinc-doped indium oxide have been grown by thermal treatments of compacted InN and ZnO powders at temperatures between 700:and 900 degrees C Under argon flow. X-ray diffraction (XRD) measurements and energy-dispersive X-ray (EDS[...]texto impreso
Rodríguez Fernández, Beatriz ; Hidalgo Alcalde, Pedro ; Piqueras de Noriega, Javier ; Méndez Martín, Bianchi | Royal Society of Chemistry | 2020-03-23The growth mechanism of layered alpha-MoO_3 nano- and microplates on the surface of Mo wires during Joule heating has been investigated by application of an external electric field to the current carrying wire. The observed rapid growth of the s[...]texto impreso
Garcia, J. A. ; Remon, A. ; Piqueras de Noriega, Javier | American Institute of Physics | 1987-10-01The effect of the addition of Bi and Mn on the photoluminescence from ZnO ceramics has been investigated. The effect of the presence of impurities on the green luminescence band can be compared to the effect of oxidizing treatments. A narrow gre[...]texto impreso
Castaldini, A. ; Cavallini, A. ; Fraboni, B ; Piqueras de Noriega, Javier ; Méndez Martín, Bianchi | IOP publishing ltd | 1994Homogeneity, distribution and nature of defects in GaAs:Te wafers with different doping concentrations have been investigated by SPV (Surface PhotoVoltage) and EBIC (Electron Beam Induced Current) methods. The resulting radial distribution of th[...]texto impreso
Zaldivar, M.H. ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | IOP publishing ltd | 1998-08The effect of indentation on the cathodoluminescence (CL) of GaN:Si epitaxial films has been investigated in the scanning electron microscope. Deformation produces changes in the defect structure which are monitored through the changes induced i[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Vicent López, José Luis ; Piqueras de Noriega, Javier ; Dieguez, E. | IOP publishing ltd | 2007-01-07The influence of the doping level on the radiative recombination properties of GaSb:Se crystals has been investigated by cathodoluminescence (CL) microscopy and spectroscopy in the scanning electron microscope. CL images evidence a high dislocat[...]texto impreso
Hidalgo Alcalde, Pedro ; Méndez Martín, Bianchi ; Piqueras de Noriega, Javier ; Dutta, P. S. ; Dieguez, E. | IOP publishing ltd | 1997Cathodoluminescence (CL) in the scanning electron microscope (SEM) has been used to investigate the effect of doping with chromium and vanadium on the native accepters and on the general structure of extended defects of gallium antimonide single[...]texto impreso
Vásquez, G. Cristian ; Andrea Peche-Herrero, M. ; Maestre Varea, David ; Alemán Llorente, Belén ; Ramirez-Castellanos, Julio ; Cremades Rodríguez, Ana Isabel ; Gonzalez-Calbet, José M. ; Piqueras de Noriega, Javier | Royal Soc. Chemistry | 2014Anatase TiO_2 nanoparticles doped with Al or Fe have been synthesized via a modified Pechini method which allows to reach high control in size and composition. Microstructural analysis onfirms the good crystallinity of the doped anatase nanopar[...]texto impreso
Gonzalo, Alicia ; Nogales Díaz, Emilio ; Méndez Martín, Bianchi ; Piqueras de Noriega, Javier | Wiley-V C H Verlag Gmbh | 2014-02Mn doped –Ga_2O_3 nanowires have been obtained by a thermal evaporation method on a gallium oxide substrate. The growth temperature has been varied in the range 1300-1500 ºC. The morphology of the resulting structures has been found to depend on[...]texto impreso
Piqueras de Noriega, Javier ; Sotillo Buzarra, Belén ; Ortega Villafuerte, Yanicet ; Fernández Sánchez, Paloma | RSC Royal Society of Chemistry | 2013Pure and In-doped ZnS structures have been grown using a VS method. Thermal treatments have been performed at temperatures ranging from 1000 to 1200 °C, during 15 to 17 hours in a N_2 overpressure environment. Nanowires and nanoribbons are the m[...]