The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Stephan Rauschenbach - One of the best experts on this subject based on the ideXlab platform.
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soft landing electrospray Ion Beam depositIon of sensitive oligoynes on surfaces in vacuum
International Journal of Mass Spectrometry, 2015Co-Authors: Gordon Rinke, Stephan Rauschenbach, Stephen Schrettl, Tobias N Hoheisel, Jonathan Blohm, Rico Gutzler, Federico Rosei, Holger Frauenrath, Klaus KernAbstract:Characterizing the complex structure of such molecules with highly resolving, vacuum-based methods like scanning probe microscopy requires their transfer into the gas phase and further onto an atomically clean surface in ultrahigh vacuum without causing additIonal contaminatIon. ConventIonally this is done via sublimatIon in vacuum. However, similar to biological molecules, large synthetic compounds can be non-volatile and decompose upon heating. Soft-landing Ion Beam depositIon using soft IonizatIon methods represents an alternative approach to vacuum depositIon. Using different oligoyne derivatives of the form of R-1-(C equivalent to C)(n)-R-2, here we demonstrate that even sensitive molecules can be handled by soft-landing electrospray Ion Beam depositIon. We generate intact molecular Ions as well as fragment Ions with intact hexayne parts and deposit them on clean metal surfaces. Scanning tunneling microscopy shows that the reactive hexayne segments of the molecules of six conjugated triple bonds are intact. The molecules agglomerate into ribbon-like islands, whose internal structure can be steered by the choice of the substituents. Our results suggest the use of Ion Beam depositIon to arrange reactive precursors for subsequent polymerizatIon reactIons. (C) 2014 The Authors. Published by Elsevier B.V.
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Crystalline inverted membranes grown on surfaces by electrospray Ion Beam depositIon in vacuum
Advanced Materials, 2012Co-Authors: Stephan Rauschenbach, Gordon Rinke, Pedro Martins De Almeida Rollo, Robert Dinnebier, R. Thomas Weitz, Nikola Malinowski, Zhitao Deng, Nicha Thontasen, Theresa Lutz, Giovanni CostantiniAbstract:Crystalline inverted membranes of the nonvolatile surfactant sodium dodecylsulfate are found on solid surfaces after electrospray Ion Beam depositIon (ES-IBD) of large SDS clusters in vacuum. This demonstrates the equivalence of ES-IBD to conventIonal molecular Beam epitaxy.
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Electrospray Ion Beam depositIon and mass spectrometry of nonvolatile molecules and nanomaterials
2008Co-Authors: Stephan RauschenbachAbstract:The vacuum depositIon of complex functIonal molecules and nanoparticles by thermal sublimatIon is often hindered due to their extremely low vapor pressure. This especially impedes the applicatIon of ultrahigh vacuum (UHV) based analytical and surface modificatIon techniques for the investigatIon of these extremely interesting systems. On the other hand, specimen prepared under ambient conditIons or in solutIon are typically not sufficiently well-defined and clean to allow a thorough and precise characterizatIon. In order to bridge this technological gap, a novel Ion Beam source for controlled soft landing depositIon in ultrahigh vacuum is constructed. The Ion Beam of nonvolatile particles is created by electrospray IonizatIon (ESI). The depositIon apparatus consists of six differential pumping stages designed to overcome the pressure difference of 13 orders of magnitude between the ambient pressure side, where IonizatIon occurs, and the high or ultrahigh vacuum, where the depositIon takes place. A variety of Ion optical devices is employed to form, mass select and guide the Ion Beam through the pumping stages onto the depositIon target. The Ion Beam is sampled from a supersonic expansIon by a skimmer, collimated in a high pressure quadrupole Ion guide, mass selected in a low pressure quadrupole Ion guide and focused by electrostatic lenses. In order to have full control over all relevant parameters, the Ion Beam is characterized before the depositIon by a linear time-of-flight mass spectrometer and a retarding grid energy detector. The flux, the compositIon and the kinetic energy of the Ion Beam can thus be measured and adjusted. The concept of Ion Beam depositIon in high and ultrahigh vacuum is demonstrated by extensive mass spectrometric and depositIon experiments. Many different types of Ion Beams, for instance composed of organic molecules, organic and inorganic Ionically bound clusters, polymers and proteins, are created by ESI. Their properties are analyzed by mass spectrometry, with special focus on their behavior upon energetic collisIons with a neutral gas, since these processes bear many similarities to collisIons with a solid surface. Some of the Ion Beams are used for depositIon. Ion Beams of the protein BSA , of the dye molecule Rhodamine 6G (Rho6G), of organic Ionic surfactant clusters composed of sodium-dodecyl sulfate (SDS) and of inorganic nanoparticles (gold colloids, carbon nanotubes, CdS nanorods and V2O5 nanowires), are deposited onto graphite and silicon oxide (SiOx) surfaces in high vacuum. The fluorescence of Rho6G is detected after its depositIon, which is a proof for the destructIon-free Ion Beam depositIon, i.e. of a successful soft landing. For the other classes of deposited particles, diffusIon on the surface and sometimes formatIon of nanostructures is observed. BSA forms fractal agglomeratIons on graphite, while it does not show any diffusIon on SiOx surfaces. SDS forms flat, two dimensIonal islands on graphite and silicon. Finally it is demonstrated that large, inorganic nanoparticles (up to 106 µ) can be Ionized and soft landed by the developed apparatus. Having proven the principle of low energy Ion Beam depositIon for a wide variety of nonvolatile particles, the technique is now ready for being integrated with in-situ characterizatIon techniques such as scanning tunneling and atomic force microscopy (STM, AFM). For this purpose, the Ion Beam depositIon setup has been expanded by two vacuum chambers for sample preparatIon and analysis. Future experiments aim at the depositIon and analysis of complex organic molecules in UHV, and at gaining a more detailed understanding of the soft landing process.
Klaus Kern - One of the best experts on this subject based on the ideXlab platform.
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soft landing electrospray Ion Beam depositIon of sensitive oligoynes on surfaces in vacuum
International Journal of Mass Spectrometry, 2015Co-Authors: Gordon Rinke, Stephan Rauschenbach, Stephen Schrettl, Tobias N Hoheisel, Jonathan Blohm, Rico Gutzler, Federico Rosei, Holger Frauenrath, Klaus KernAbstract:Characterizing the complex structure of such molecules with highly resolving, vacuum-based methods like scanning probe microscopy requires their transfer into the gas phase and further onto an atomically clean surface in ultrahigh vacuum without causing additIonal contaminatIon. ConventIonally this is done via sublimatIon in vacuum. However, similar to biological molecules, large synthetic compounds can be non-volatile and decompose upon heating. Soft-landing Ion Beam depositIon using soft IonizatIon methods represents an alternative approach to vacuum depositIon. Using different oligoyne derivatives of the form of R-1-(C equivalent to C)(n)-R-2, here we demonstrate that even sensitive molecules can be handled by soft-landing electrospray Ion Beam depositIon. We generate intact molecular Ions as well as fragment Ions with intact hexayne parts and deposit them on clean metal surfaces. Scanning tunneling microscopy shows that the reactive hexayne segments of the molecules of six conjugated triple bonds are intact. The molecules agglomerate into ribbon-like islands, whose internal structure can be steered by the choice of the substituents. Our results suggest the use of Ion Beam depositIon to arrange reactive precursors for subsequent polymerizatIon reactIons. (C) 2014 The Authors. Published by Elsevier B.V.
Giovanni Costantini - One of the best experts on this subject based on the ideXlab platform.
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Crystalline inverted membranes grown on surfaces by electrospray Ion Beam depositIon in vacuum
Advanced Materials, 2012Co-Authors: Stephan Rauschenbach, Gordon Rinke, Pedro Martins De Almeida Rollo, Robert Dinnebier, R. Thomas Weitz, Nikola Malinowski, Zhitao Deng, Nicha Thontasen, Theresa Lutz, Giovanni CostantiniAbstract:Crystalline inverted membranes of the nonvolatile surfactant sodium dodecylsulfate are found on solid surfaces after electrospray Ion Beam depositIon (ES-IBD) of large SDS clusters in vacuum. This demonstrates the equivalence of ES-IBD to conventIonal molecular Beam epitaxy.
B. M. Seredin - One of the best experts on this subject based on the ideXlab platform.
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Growth of Ga_ x In_1 − x As_ y P_1 − y /GaAs quantum dot arrays by Ion Beam depositIon
Inorganic Materials, 2014Co-Authors: I. A. Sysoev, M. L. Lunina, D. L. Alfimova, A. V. Blagin, D. A. Gusev, B. M. SeredinAbstract:Experimental data are presented that demonstrate the possibility of producing GaInAsP quantum dots on GaAs by Ion Beam depositIon. The morphology of the quantum dots and the effect of GaAs substrate temperature on parameters of GaInAsP quantum dot arrays have been studied by atomic force microscopy and scanning electron microscopy. We have determined the elemental compositIon of the quantum dots and obtained photoluminescence spectra of the GaInAsP/GaAs heterostructures.
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Growth of GaxIn1 − xAsyP1 − y/GaAs quantum dot arrays by Ion Beam depositIon
Inorganic Materials, 2014Co-Authors: I. A. Sysoev, M. L. Lunina, D. L. Alfimova, A. V. Blagin, D. A. Gusev, B. M. SeredinAbstract:Experimental data are presented that demonstrate the possibility of producing GaInAsP quantum dots on GaAs by Ion Beam depositIon. The morphology of the quantum dots and the effect of GaAs substrate temperature on parameters of GaInAsP quantum dot arrays have been studied by atomic force microscopy and scanning electron microscopy. We have determined the elemental compositIon of the quantum dots and obtained photoluminescence spectra of the GaInAsP/GaAs heterostructures.
Gordon Rinke - One of the best experts on this subject based on the ideXlab platform.
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soft landing electrospray Ion Beam depositIon of sensitive oligoynes on surfaces in vacuum
International Journal of Mass Spectrometry, 2015Co-Authors: Gordon Rinke, Stephan Rauschenbach, Stephen Schrettl, Tobias N Hoheisel, Jonathan Blohm, Rico Gutzler, Federico Rosei, Holger Frauenrath, Klaus KernAbstract:Characterizing the complex structure of such molecules with highly resolving, vacuum-based methods like scanning probe microscopy requires their transfer into the gas phase and further onto an atomically clean surface in ultrahigh vacuum without causing additIonal contaminatIon. ConventIonally this is done via sublimatIon in vacuum. However, similar to biological molecules, large synthetic compounds can be non-volatile and decompose upon heating. Soft-landing Ion Beam depositIon using soft IonizatIon methods represents an alternative approach to vacuum depositIon. Using different oligoyne derivatives of the form of R-1-(C equivalent to C)(n)-R-2, here we demonstrate that even sensitive molecules can be handled by soft-landing electrospray Ion Beam depositIon. We generate intact molecular Ions as well as fragment Ions with intact hexayne parts and deposit them on clean metal surfaces. Scanning tunneling microscopy shows that the reactive hexayne segments of the molecules of six conjugated triple bonds are intact. The molecules agglomerate into ribbon-like islands, whose internal structure can be steered by the choice of the substituents. Our results suggest the use of Ion Beam depositIon to arrange reactive precursors for subsequent polymerizatIon reactIons. (C) 2014 The Authors. Published by Elsevier B.V.
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Electrospray Ion Beam DepositIon of Complex Non-Volatile Molecules
2013Co-Authors: Gordon RinkeAbstract:Keywords: Electrospray ; Ion Beam ; DepositIon ; Scanning Tunneling Microscopy ; Ultrahigh Vacuum ; Complex Non-volatile ; Organic Molecules ; Nanostructures ; Cytochrome C ; Bradykinin ; Clusters ; Self-assembly These Ecole polytechnique federale de Lausanne EPFL, n° 5892 (2013)Programme doctoral Sciences et Genie des materiauxFaculte des sciences de baseInstitut de physique de la matiere condenseeLaboratoire de science a l'echelle nanometriqueJury: A. Mortensen (president), L. Grill, E. Meyer, F. Stellacci Public defense: 2013-9-18 Reference doi:10.5075/epfl-thesis-5892Print copy in library catalog Record created on 2013-09-09, modified on 2017-05-12
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Crystalline inverted membranes grown on surfaces by electrospray Ion Beam depositIon in vacuum
Advanced Materials, 2012Co-Authors: Stephan Rauschenbach, Gordon Rinke, Pedro Martins De Almeida Rollo, Robert Dinnebier, R. Thomas Weitz, Nikola Malinowski, Zhitao Deng, Nicha Thontasen, Theresa Lutz, Giovanni CostantiniAbstract:Crystalline inverted membranes of the nonvolatile surfactant sodium dodecylsulfate are found on solid surfaces after electrospray Ion Beam depositIon (ES-IBD) of large SDS clusters in vacuum. This demonstrates the equivalence of ES-IBD to conventIonal molecular Beam epitaxy.
