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  • 1. Ausen, Dag
    et al.
    Westvik, Rita
    Svagård, Ingrid
    Österlund, Lars
    Gustafson, Inga
    Vikholm-Lundin, Inger
    Winquist, Fredrik
    Lading, Lars
    Gran, Jens
    Foresight Biomedical Sensors2007Report (Other academic)
    Abstract [en]

    The foresight study on biomedical sensors has addressed different approaches with future use of biomedical sensors in the health care sector, like: How will biomedical sensors shape the healthcare systems of the future? How can they impact the quality and cost of healthcare and what are the business opportunities in the Nordic region?

  • 2.
    Boyadjiev, Stefan I.
    et al.
    “Georgi Nadjakov” Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko chaussee Blvd., 1784 Sofia, Bulgaria.
    Stefan, Nicolaie
    National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, RO-77125, Magurele-Ilfov, Romania.
    Stan, George
    National Institute of Materials Physics, 405A Atomistilor Street, Magurele-Ilfov, RO-077125, Romania.
    Arvizu, Miguel
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Szilágyi, Imre M.
    MTA-BME Technical Analytical Chemistry Research Group, Szent Gellért tér 4., H-1111, Budapest, Hungary and Budapest University of Technology and Economics, Department of Inorganic and Analytical Chemistry, 4 Műegyetem rakpart, H-1111, Budapest, Hungary.
    Visan, Anita
    National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, RO-77125, Magurele-Ilfov, Romania.
    Mihailescu, Natalia
    National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, RO-77125, Magurele-Ilfov, Romania.
    Mihailescu, Ion N.
    National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, RO-77125, Magurele-Ilfov, Romania.
    Besleaga, Cristina
    National Institute of Materials Physics, 405A Atomistilor Street, Magurele-Ilfov, RO-077125, Romania.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Gesheva, Kostadinka A.
    Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tzarigradsko chaussee Blvd., 1784 Sofia, Bulgaria.
    Study of the electrochromic properties of MAPLE and PLD deposited WO3 thin films2017Conference paper (Refereed)
    Abstract [en]

    Tungsten trioxide (WO3) thin films were grown by matrix assisted pulsed laser evaporation (MAPLE) and pulsed laser deposition (PLD), and their properties were investigated for electrochromic applications. The structure, morphology and optical properties of these MAPLE and PLD grown from monoclinic WO3 nano-sized particles WO3 thin films were also studied. A KrF* excimer (λ=248 nm, ζFWHM=25 ns) laser source was used in all experiments. The films were studied by atomic force microscopy (AFM), grazing incidence X-ray diffraction (GIXRD) and Fourier transform infrared spectroscopy (FTIR). Cyclic voltammetry measurements were also performed in glove box with Ar atmosphere towards Li electrode, and the coloring and bleaching states were investigated. The morpho-structural investigations disclosed the synthesis of single-phase monoclinic WO3 films consisting of crystalline nano-grains embedded in an amorphous matrix. All thin films showed good electrochromic properties - strong coloration and fast and full bleaching. The effect was observed for many cycles, the strong coloration and full bleaching being preserved. These results are promising for future application of MAPLE and PLD deposited WO3 thin films in the development of electrochromic devices.

  • 3.
    Cai, Yixiao
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Lendel, Christofer
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kasrayan, Alex
    Lannfelt, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Ingelsson, Martin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Karlsson, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Bergström, Joakim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Changes in secondary structure of α-synuclein during oligomerization induced by reactive aldehydes.2015In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 464, no 1, p. 336-341Article in journal (Refereed)
    Abstract [en]

    The oxidative stress-related reactive aldehydes 4-hydroxy-2-nonenal (HNE) and 4-oxo-2-nonenal (ONE) have been shown to promote formation of α-synuclein oligomers in vitro. However, the changes in secondary structure of α-synuclein and the kinetics of the oligomerization process are not known and were the focus of this study. Size exclusion chromatography showed that after 1 h of incubation, HNE induced the formation of an oligomeric α-synuclein peak with a molecular weight of about ∼2000 kDa, which coincided with a decreasing ∼50 kDa monomeric peak. With prolonged incubation (up to 24 h) the oligomeric peak became the dominating molecular species. In contrast, in the presence of ONE, a ∼2000 oligomeric peak was exclusively observed after 15 min of incubation and this peak remained constant with prolonged incubation. Western blot analysis of HNE-induced α-synuclein oligomers showed the presence of monomers (15 kDa), SDS-resistant low molecular (30-160 kDa) and high molecular weight oligomers (≥260 kDa), indicating that the oligomers consisted of both covalent and non-covalent protein. In contrast, ONE-induced α-synuclein oligomers only migrated as covalent cross-linked high molecular-weight material (≥300 kDa). Both circular dichroism (CD) and Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy showed that the formation of HNE- and ONE-induced oligomers coincided with a spectral change from random coil to β-sheet. However, ONE-induced α-synuclein oligomers exhibited a slightly higher degree of β-sheet. Taken together, our results indicate that both HNE and ONE induce a change from random coil to β-sheet structure that coincides with the formation of α-synuclein oligomers. Albeit through different kinetic pathways depending on the degree of cross-linking.

  • 4.
    Geremariam Welearegay, Tesfalem
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics. Rovira & Virgili Univ, Dept Elect Elect & Automat Engn, Tarragona 43007, Spain.;Mol Fingerprint Sweden AB, S-75655 Uppsala, Sweden..
    Cindemir, Umut
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics. Mol Fingerprint Sweden AB, S-75655 Uppsala, Sweden.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics. Mol Fingerprint Sweden AB, S-75655 Uppsala, Sweden.
    Ionescu, Radu
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics. Rovira & Virgili Univ, Dept Elect Elect & Automat Engn, Tarragona 43007, Spain..
    Fabrication and characterisation of ligand-functionalised ultrapure monodispersed metal nanoparticle nanoassemblies employing advanced gas deposition technique2018In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 29, no 6, article id 065603Article in journal (Refereed)
    Abstract [en]

    Here, we report for the first time the fabrication of ligand-functionalised ultrapure monodispersed metal nanoparticles (Au, Cu, and Pt) from their pure metal precursors using the advanced gas deposition technique. The experimental conditions during nanoparticle formation were adjusted in order to obtain ultrafine isolated nanoparticles on different substrates. The morphology and surface analysis of the as-deposited metal nanoparticles were investigated using scanning electron microscopy, x-ray diffraction and Fourier transform infra-red spectroscopy, which demonstrated the formation of highly ordered pure crystalline nanoparticles with a relatively uniform size distribution of similar to 10 nm (Au), similar to 4 nm (Cu) and similar to 3 nm (Pt), respectively. A broad range of organic ligands containing thiol or amine functional groups were attached to the nanoparticles to form continuous networks of nanoparticle-ligand nanoassemblies, which were characterised by scanning electron microscopy and x-ray photoelectron spectroscopy. The electrical resistance of the functional nanoassemblies deposited in the gap spacing of two microfabricated parallel Au electrodes patterned on silicon substrates ranged between tens of k Omega and tens of M Omega, which is suitable for use in many applications including (bio)chemical sensors, surface-enhanced Raman spectroscopy and molecular electronic rectifiers.

  • 5.
    Guziewicz, Elzbieta
    et al.
    Polish Acad Sci, Inst Phys, Warsaw, Poland.
    Paskaleva, Albena
    Bulgarian Acad Sci, Inst Solid State Phys, Sofia, Bulgaria.
    Knez, Mato
    Basque Fdn Sci, Ikerbasque, San Sebastian, Spain.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Advanced Oxide Materials - Growth, Application, Characterization2018In: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 215, no 16, article id 1800546Article in journal (Other academic)
  • 6.
    Haas, Julian
    et al.
    Ulm University, Germany.
    Vargas Catalan, Ernesto
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Piron, Pierre
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Karlsson, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Mizaikoff, Boris
    Ulm University, Germany.
    Polycrystalline diamond thin-film waveguides for mid-infrared evanescent field sensors2018In: ACS Omega, ISSN 2470-1343, Vol. 3, no 6, p. 6190-6198Article in journal (Refereed)
    Abstract [en]

    Photonic design and optimization of thin-film polycrystalline diamond waveguides are shown, serving as advanced evanescent field transducers in the mid-infrared fingerprint regime (2000-909 cm(-1); 5-11 mu m). Design constraints inherent to optical/system considerations and the material were implemented in a finite element method (FEM)-based simulation method that allowed three-dimensional modeling of the overall structure. Thus, lateral mode confinement, attenuation in the direction of radiation propagation, and physical resilience were evaluated. In a final step, the designed structures were fabricated, and their utility in combination with a broadly tunable external cavity quantum cascade laser for chemical sensing of a liquid phase analyte was demonstrated.

  • 7.
    Henych, Jiri
    et al.
    Czech Acad Sci, Inst Inorgan Chem, Mat Chem Dept, Husinec Rez 1001, Rez 25068, Czech Republic.
    Stengl, Vaclav
    Czech Acad Sci, Inst Inorgan Chem, Mat Chem Dept, Husinec Rez 1001, Rez 25068, Czech Republic.
    Mattsson, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Tolasz, Jakub
    Czech Acad Sci, Inst Inorgan Chem, Mat Chem Dept, Husinec Rez 1001, Rez 25068, Czech Republic.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Chemical warfare agent simulant DMMP reactive adsorption on TiO2/graphene oxide composites prepared via titanium peroxo-complex or urea precipitation2018In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 359, p. 482-490Article in journal (Refereed)
    Abstract [en]

    Two water-based methods were used to produce TiO2/graphene oxide (GO) nanocomposites with 1 and 2 wt.% GO. Both procedures exclude the use of organometallic precursors, as well as the high-pressure and high-temperature treatments, which facilitate pure and energy efficient synthesis amenable for larger scale synthesis. Nanocomposites with narrow (< 10 nm) and long spindle-like (< 100 nm) TiO2 nanoparticles supported on GO flakes were obtained (TiO2/GO), and their properties for reactive destruction of the organophosphorus simile chemical warfare agent (CWA) dimethyl methylphosphonate (DMMP) were investigated by in situ DRIFTS spectroscopy. Both synthesis procedures yielded highly reactive nanocomposites with markedly different properties compared to similarly prepared pure TiO2 nanoparticles. GO also induced morphology and texture changes, which were observed to have a significant impact on the adsorption and reactivity of the nano composites, and which were strongly related to synthesis procedure. In particular, the reduction state of GO, as measured by Raman spectroscopy, was observed to play a major role for the reactivity of the TiO2/GO nano composites.

  • 8.
    Jamil, Tarek S.
    et al.
    National Research Center, Water Pollution Control Department, National Research Center, El Buhouth Street, P.O. Box 12311, Dokki, Cairo, Egypt.
    Ghaly, Montaser Y.
    Chemical Engineering and Pilot Plant Department, National Research Centre, Egypt.
    Fathy, Nady A.
    Surface Chemistry and Catalysis Laboratory, National Research Centre, Egypt.
    Abd el-halim, Tarek A.
    Surface Morphology and Elemental Analysis Department, Nuclear Material Authority, Egypt.
    Österlund, Lars
    FOI CBRN Defence and Security, SE-901 82 Umeå, Sweden.
    Enhancement of TiO2 behavior on photocatalytic oxidation of MO dye using TiO2/AC under visible irradiation and sunlight radiation2012In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 98, p. 270-279Article in journal (Refereed)
    Abstract [en]

    The activated carbon loaded TiO2 photocatalyst was prepared and characterized by FT-IR, scanning electron micrograph (SEM) and X-ray diffraction (XRD). The photocatalytic efficiency of activated carbon loaded TiO2 was evaluated by photocatalytic oxidation of Methyl Orange (MO) dye in aqueous medium using visible and solar light. TiO2/AC exhibited higher photocatalytic oxidation efficiency of MO than that of naked TiO2. The various experimental parameters like initial dye concentration, amount of catalyst and solution pH for efficient dye degradation are investigated. Activity measurements performed under visible light and solar irradiation have shown good results for the photo degradation of MO in aqueous solution. The higher efficiency of TiO2/AC is due to synergy effect of activated carbon. Addition of high adsorption capacity activated carbon to photoactive titanium dioxide in photocatalytic degradation of dyes improves the efficiency of dye mineralization. The present catalysts show high adsorptivity and high photoactivity for the degradation of the MO dye and can be very easily separated from the solution by sedimentation or simple filtration and it can be used repeatedly for MO removal with preservation of its photoactivity.

  • 9.
    Johansson, Malin B.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Mattsson, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Lindquist, Sten-Eric
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Niklasson, Gunnar A.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    The Importance of Oxygen Vacancies in Nanocrystalline WO3−x ThinFilms Prepared by DC Magnetron Sputtering for Achieving High Photoelectrochemical Efficiency2017In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 121, no 13, p. 7412-7420Article in journal (Refereed)
    Abstract [en]

    The photoelectrochemical properties of tungsten oxide thinfilms with different stoichiometry (WO3−x) and thickness were investigated.The films were sputtered in O2/Ar gas (ratio 0.43) on glass substrates coatedwith fluorine-doped tin dioxide at two sputter pressures, Ptot = 10 and 30mTorr, yielding O/W ratios of the films, averaged over three samples, of 2.995and 2.999 (x ∼ 0.005 and x ∼ 0.001), respectively. The films were characterizedby X-ray diffraction, scanning electron microscopy, and spectrophotometry.The 10 mTorr samples showed large absorption in the near-infrared (NIR)range, whereas the 30 mTorr samples had a small absorption in this region. Theconcentration of oxygen vacancy band gap states was estimated from cyclicvoltammetry and was found to correlate with the optical absorption in the NIRregion. The incident photon to current efficiency for illumination from theelectrolyte side (IPCEEE) and substrate electrode side (IPCESE) showed higherefficiency for the more stoichiometric films, indicating that oxygen vacancies in the band gap act as recombination centers.Surprisingly high values of IPCEEE and IPCESE were found, and it was concluded that efficient charge separation and transporttake place almost throughout the entire film even for film electrodes as thick as 2 μm. Analysis of the spectral distribution of thephotoresponse (action spectra) using an extended Gärtner−Butler model to calculate the IPCE for front-side and back-sideillumination was performed and showed that the diffusion length is large, of the order of the depletion layer thickness.

  • 10.
    Johansson, Malin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kristiansen, Paw T.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Niklasson, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Band gap states in nanocrystalline WO3 thin films studied by softx-ray spectroscopy and opticalspectrophotometry2016In: Journal of Physics: Condensed Matter, ISSN 1361-648X, Vol. 28, article id 475802Article in journal (Refereed)
    Abstract [en]

    Nanocrystalline tungsten trioxide (WO3) thin films prepared by DC magnetron sputteringhave been studied using soft x-ray spectroscopy and optical spectrophotometry. Resonantinelastic x-ray scattering (RIXS) measurements reveal band gap states in sub-stoichiometric γ-WO3−x with x = 0.001–0.005. The energy positions of these states are in good agreementwith recently reported density functional calculations. The results were compared with opticalabsorption measurements in the near infrared spectral region. An optical absorption peak at 0.74 eV is assigned to intervalence transfer of polarons between W sites. A less prominentpeak at energies between 0.96 and 1.16 eV is assigned to electron excitation of oxygenvacancies. The latter results are supported by RIXS measurements, where an energy loss inthis energy range was observed, and this suggests that electron transfer processes involvingtransitions from oxygen vacancy states can be observed in RIXS. Our results have implicationsfor the interpretation of optical properties of WO3, and the optical transitions close to the bandgap, which are important in photocatalytic and photoelectrochemical applications.

  • 11.
    Lebrun, Delphine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Demonstration of Slow Photon Chemistry on Multilayer Inverse Opals2017In: Science of Advanced Materials, ISSN 1947-2935, E-ISSN 1947-2943, Vol. 9, no 11, p. 1947-1952Article in journal (Refereed)
    Abstract [en]

    We demonstrate the use of atomic layer deposited multilayered alumina/titania photonic crystals for stearicacid (SA) degradation using broadband light illumination. The degradation of SA was monitored every 15 minutes by Fourier transform infrared spectroscopy, using a simple rotation of the sample holder to switchbetween light source and infrared probing beam. We analyzed four samples with different photonic bandgap(PBG) positions, from 397 to 372 nm, with different titania layer thicknesses, but otherwise prepared in identicalmanner. With this approach the photonic efficiency (PE) could readily be calculated without having to considerdifferent sample preparation procedure. We found that a sample with a high-energy edge of the PBG positionoverlapping with the electronic bandgap position of titania (Eg∼ 385 nm) and the highest photon power of ourlight source had the highest PE = 0.002. Comparison with the other samples shows that the slow photon effectapparent at the PBG edge can explain the higher PE, and suggest that bandgap engineering of multilayerphotonic materials is a practically viable method to improve the efficiency of a photocatalyst.

  • 12.
    Mattsson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Hu, Shuanglin
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Hermansson, Kersti
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Adsorption and photodecomposition of formic acid on rutile TiO2 (110) surfaces2013Conference paper (Other academic)
  • 13.
    Mattsson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Co-adsorption of oxygen and formic acid on rutile TiO2 (110) studied by infrared reflection-absorption spectroscopy2017In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 663, p. 47-55Article in journal (Refereed)
    Abstract [en]

    Adsorption of formic acid and co-adsorption with oxygen have been investigated on the rutile TiO2(110) surface using p- and s-polarized infrared reflection-absorption spectroscopy (IRRAS) at O2 exposures between 45 L to 8100 L and at temperatures between 273 K and 343 K. On the clean surface formic acid dissociates into a formate ion (formate) and a proton. Formate binds to two five-fold coordinated Ti atoms in the troughs along the [001] direction, and the proton binds to neighboring bridging O atoms. Exposure of adsorbed formate to O2 leads to a decrease in the asymmetric νas(OCO) band at 1532 cm−1 and to the concomitant formation of a new vibration band at 1516 cm−1. From the s-and p-polarized IRRAS measurements performed at different O2 exposures, surface pre-treatments and substrate temperatures, and by comparisons with previous reports, we conclude that the new species is a bidentate surface hydrogen carbonate, which is formed by reaction between formate and oxygen adatoms on the surface. The σv reflection plane of the surface hydrogen carbonate molecule is oriented along the [001] direction, i.e. the same direction as the adsorbed formate molecule. On the clean TiO2(110) surface exposed to O2 prior to formic acid adsorption, similar results are obtained. The reaction rate to form surface hydrogen carbonate from formate is found to follow first-order kinetics, with an apparent activation energy of Er=0.25 eV.

    The full text will be freely available from 2019-04-28 00:00
  • 14.
    Mattsson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Formic acid adsorption and photo-induced decomposition on TiO2: A comparative study of rutile single crystals, sputtered and sol-gel synthesized anatase, brookite and rutile thin filmsManuscript (preprint) (Other academic)
  • 15.
    Mattsson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Infrared reflection-absorption spectroscopy study of HCOOH/TiO2 (110): Photo-reactions on stoichiometric and defective surfaces2014Conference paper (Other academic)
  • 16.
    Mattsson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Infrared Reflection-Absorption Spectroscopy Study of the Interaction between O2 and Formic Acid on Rutile TiO2 (110) Surfaces2016Conference paper (Refereed)
    Abstract [en]

    Formic acid adsorption on rutile TiO2(110) single crystals exposed to different oxygen partial pressures have been investigated with infrared reflection-absorption spectroscopy (IRRAS) employing p- and s-polarized light incident along the [001] crystal direction at a temperatures between 273K and 303K. IRRAS spectra, prior to oxygen exposure, shows that formic acid dissociates upon adsorption and binds to the surface as bridging formate species with the symmetric νs(OCO) and asymmetric νas(OCO) peak at 1360 and 1531 cm-1, respectively. A new asymmetric νas(OCO) band at 1517 cm-1develops in the presence of O2, which is correlated with the O2 partial pressure, whereas no changes is seen in the symmetric νs(OCO) band. At low O2 pressures(<1 ×10-7mbar), this band is not detectable within 3 h of O2 exposure. At higher O2pressures, 5 ×10-7 mbar, the band starts to develop, and at 1 ×10-6 mbar, a pronounced band develops after 30 min exposure. The O2 induced band at 1517 cm-1 does not disappear as the O2 gas is removed, suggesting that a stable chemical modification of adsorbed formate molecules. No changes were observed in the s-polarized IRRAS spectra with O2 exposure, showing that there is no rotation of the formate molecules in the plane of the surface. The appearance of the new νas(OCO) band are consistent with a model where O2 dissociated to form O adatoms bonded to the Ti5c atoms, which interact with bridging formate molecules bonded along the [001] direction. The relationship between the oxygen partial pressure and the formation of this new band is due to the increased larger interaction between the surface and the oxygen with increase pressure or an increased oxygenation of formate. Our results provide new insight into the interaction between O2and TiO2surfaceat elevated pressures relevant for practical applications.

  • 17.
    Piron, Pierre
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Vargas Catalan, Ernesto
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Haas, Julian
    Ulm University, Germany.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nikolajeff, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Andersson, Per Ola
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Bergström, Joakim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Geriatrics.
    Mizaikoff, Boris
    Ulm University, Germany.
    Karlsson, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Development of a diamond waveguide sensor for sensitive protein analysis using IR quantum cascade lasers2018In: SPIE Proceedings Volume 10539: Photonic Instrumentation, Engineering V / [ed] Yakov G. Soskind, 2018Conference paper (Refereed)
  • 18.
    Sayhi, Maher
    et al.
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.; Faculté des Sciences de Tunis, Campus Universitaire El-Manar, 2092 El Manar, Tunis, Tunisia.;Université Tunis El Manar, Tunis 1068, Tunisia.
    Ouerghi, Oussama
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.; Prince Sattam Bin Abdulaziz University, Saudi Arabia.
    Belgacem, Kamel
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.;Université Tunis El Manar, Tunis 1068, Tunisia.
    Arbi, Marwa
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.;Université Tunis El Manar, Tunis 1068, Tunisia.
    Tepeli, Yudum
    Chemistry Department, Faculty of Science, Muğla Sıtkı Koçman University, Kotekli, Mugla, Turkey.
    Ghram, Abdeljalil
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.;Université Tunis El Manar, Tunis 1068, Tunisia.
    Anik, Ülkü
    Chemistry Department, Faculty of Science, Muğla Sıtkı Koçman University, Kotekli, Mugla, Turkey.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Laouini, Dhafer
    Université Tunis El Manar, Tunis 1068, Tunisia.;Institut Pasteur de Tunis, LR11IPT02, Laboratory of Transmission, Control and Immunobiology of Infections (LTCII), Tunis-Belvédère 1002, Tunisia.
    Diouani, Mohamed Fethi
    Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia.;Université Tunis El Manar, Tunis 1068, Tunisia.
    Electrochemical detection of influenza virus H9N2 based on both immunomagnetic extraction and gold catalysis using an immobilization-free screen printed carbon microelectrode2018In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 107, p. 170-177Article in journal (Refereed)
    Abstract [en]

    Influenza is a viral infectious disease considered as a source of many health problems and enormous socioeconomic disruptions. Conventional methods are inadequate for in-field detection of the virus and generally suffer from being laborious and time-consuming. Thus, studies aiming to develop effective alternatives to conventional methods are urgently needed. In this work, we developed an approach for the isolation and detection of influenza A virus subtype H9N2. For this aim, two specific influenza receptors were used. The first, anti-matrix protein 2 (M2) antibody, was attached to iron magnetic nanoparticles (MNPs) and used for the isolation of the virus from allantoic fluid. The second biomolecule, Fetuin A, was attached to an electrochemical detectable label, gold nanoparticles (AuNPs), and used to detect the virus tacking advantage from fetuin-hemagglutinin interaction. The MNP-Influenza virus-AuNP formed complex was isolated and treated by an acid solution then the collected gold nanoparticles were deposited onto a screen printed carbon electrode. AuNPs catalyzes the hydrogen ions reduction in acidic medium while applying an appropriate potential, and the generated current signal was proportional to the virus titer. This approach allows the rapid detection of influenza virus A/H9N2 at a less than 16 HAU titer.

  • 19.
    Sobetkii, A. A.
    et al.
    National R&D Institute for Nonferrous and Rare Metals, Rumania.
    Piticescu, R. M.
    National R&D Institute for Nonferrous and Rare Metals, Rumania.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Cindemir, Umut
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Ulieru, D.
    National R&D Institute for Nonferrous and Rare Metals, Rumania.
    Rusti, C.F.
    National R&D Institute for Nonferrous and Rare Metals, Rumania.
    GD and DC Reactive Sputtering synthesis of WO3 thin films for gas sensors2016In: GD and DC Reactive Sputtering synthesis of WO3 thin films for gas sensors, 2016Conference paper (Refereed)
  • 20.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Catalytic self-cleaning films for the built environment: Combining facet-texturing, acid-base functionalization and spectral selectivity2017Conference paper (Refereed)
    Abstract [en]

    The possibility to increase human comfort and reduce the global footprint of buildings is a powerful driving force for introduction of new building technology. Here advanced coating technologies play an important role. We demonstrate here that photocatalytic and self-cleaning films can be tailored such that they can be up-scaled with available sputtering technologies. Three approaches to achieve these improved functions are presented. First, we show that facet-texturing to increase the fraction of exposed {001} increases the catalytic activity up to one order of magnitude [1]. In a second approach, surface functionalization of the films by sulfate and nitrate groups renders the surfaces resilient towards deactivation in dry conditions by a proton transfer mechanism [2,3]. In such films bonding of acidic intermediates originating VOC pollutants is avoided which otherwise deactivate their surfaces. In addition, the wetting properties of the TiO2 films are also modified to make them repel e.g. fatty acids and thus possess excellent anti-greasing functionality [4]. In the third approach, TiO2 is deposited on visible-infrared light absorbing films, whereby heat generated in the underlying light absorbing film heats the TiO2 film. We show that increasing the temperature of the TiO2 film results in an increased photocatalytic activity by two mechanisms: thermal activation to increase reaction kinetics, and by shifting the water gas-surface equilibrium coverage to free surface sites for reactant molecules. We generalize the results, and discuss their implications for green building technology and possible scenarios for their implementation.

    [1] B. Stefanov, G. Niklasson, C.G. Granqvist, L. Österlund, J. Mater. Chem. A 2015, 3, 17369-17375.

    [2] B. I. Stefanov, J. Maibach, Z. Topalian, G. A. Niklasson, C. G. Granqvist, L. Österlund, ACS Catal., submitted.

    [3] Z. Topalian, B. Stefanov, C.G. Granqvist, and L. Österlund, J. Catal. 2013, 307, 265-274.

    [4] Z. Topalian, G. Niklasson, and L. Österlund, ACS Appl. Mater. Interfaces 2012, 4, 672−679.

  • 21.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Mid-infrared diamond waveguides and affinitiy layers on them2017Conference paper (Other academic)
1 - 21 of 21
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