TITLE

Experimental evidence of a two-step reversible absorption/desorption process in ruthenium phtalocyanine gas sensing films by in situ energy dispersive x-ray reflectometry

AUTHOR(S)
Generosi, A.; Paci, B.; Rossi Albertini, V.; Perfetti, P.; Pennesi, G.; Paoletti, A. M.; Rossi, G.; Capobianchi, A.; Caminiti, R.
PUB. DATE
March 2005
SOURCE
Applied Physics Letters;3/14/2005, Vol. 86 Issue 11, p114106
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
An in situ energy dispersive x-ray reflectivity technique was used to study the morphological changes of gas sensing thin films of ruthenium phtalocyanine (RuPc)2 induced by gas absorption/desorption processes. The time-resolved collection of reflectivity spectra during the exposure of each film to a gas flux of nitrogen oxides provided the evolution of the morphological parameters (thickness and roughness). The gas absorption process develops in two stages: The first induces morphological changes characteristic of a surface (adsorption) process, while the second is dominated by a bulk effect. This two-step behavior is also observed in the desorption process: When the thermal treatment is performed at 130 °C, the gas is released from the bulk only. Conversely, at higher temperatures, the gas is fully released, i.e., also from the surface, and the initial film thickness is regained. Finally, a further in situ study upon a second absorption treatment was carried out: In this case, only the film bulk diffusion process takes place.
ACCESSION #
16581614

 

Related Articles

  • Revealing hidden pore structure in nanoporous thin films using positronium annihilation lifetime spectroscopy. Peng, Hua-Gen; Frieze, William E.; Vallery, Richard S.; Gidley, David W.; Moore, Darren L.; Carter, Richard J. // Applied Physics Letters;3/21/2005, Vol. 86 Issue 12, p121904 

    The highly inhomogeneous pore morphology of a plasma-enhanced-chemical-vapor-deposited ultralow-k dielectric film (k=2.2) has been revealed using depth-profiled positronium annihilation lifetime spectroscopy (PALS) combined with progressive etch back of the film surface. The film is found to...

  • Optical properties of switchable mirrors based on magnesium-calcium alloy thin films. Yamada, Y.; Bao, S.; Tajima, K.; Okada, M.; Yoshimura, K. // Applied Physics Letters;5/11/2009, Vol. 94 Issue 19, p191910 

    Switchable mirrors based on magnesium-calcium alloy thin films were prepared using a direct-current magnetron sputtering method and their gasochromic properties have been investigated. Pd-capped Mg1-zCaz (0.04

  • Andreev nanoprobe of half-metallic CrO2 films using superconducting cuprate tips. Turel, C. S.; Guilaran, I. J.; Xiong, P.; Wei, J. Y. T. // Applied Physics Letters;11/7/2011, Vol. 99 Issue 19, p192508 

    Superconducting tips of YBa2Cu3O7-x were used to perform point-contact Andreev reflection spectroscopy on half-metallic CrO2 thin films. At 4.2 K, strong suppression of the d-wave Andreev reflection characteristics was observed, consistent with the high spin polarization of CrO2. Our technique...

  • Electrical and optical properties of sol-gel derived ZnO:Al thin films. Sagar, P.; Kumar, M.; Mehra, R. M. // Materials Science (0137-1339);2005, Vol. 23 Issue 3, p685 

    High quality sol-gel derived ZnO and ZnO:Al thin films were deposited on coming (7059) glass substrates by spin coating. The annealed films showed the c-axis-preferred orientation. The structural, electrical, and optical properties of the films were investigated as a function of Al concentration...

  • Dye-doped polymer microring laser coupled with stimulated resonant Raman scattering. Yanagi, Hisao; Takeaki, Rei; Tomita, Satoshi; Ishizumi, Atsushi; Sasaki, Fumio; Yamashita, Kenichi; Oe, Kunishige // Applied Physics Letters;7/20/2009, Vol. 95 Issue 3, p033306 

    Polymer ring laser was fabricated with 1,4-bis[2-[4-[N,N-di(p-totyl)amino]phenyl]vinyl]benzene (DADSB)-doped polyvinyl-pyrrolidone (PVP) thin films coated on an inner surface of a quartz microcapillary. Ring-waveguided multimode lasing was observed under pulsed optical pumping. With increasing...

  • Impedance spectroscopy analysis of SnO2 thick-films gas sensors. Ponce, M. A.; Bueno, P.; Varela, J.; Castro, M.; Aldao, C. // Journal of Materials Science: Materials in Electronics;Dec2008, Vol. 19 Issue 12, p1169 

    A careful analysis of the impedance response of SnO2 thick films under vacuum and air atmosphere is reported in the present work. The AC electrical resistance was analyzed and it was shown that it is highly frequency dependent. Different models and its equivalent circuit representation were...

  • Band alignment in ultrathin Hf–Al–O/Si interfaces. Jin, H.; Oh, S. K.; Kang, H. J.; Lee, S. W.; Lee, Y. S.; Cho, M.-H. // Applied Physics Letters;11/21/2005, Vol. 87 Issue 21, p212902 

    Band alignment in Hf–Al–O thin films, grown on Si(100) by atomic layer deposition, was determined via x-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The changes in conduction band offset, valence band offset, and bandgap were obtained as a...

  • Evidence of a rearrangement of the surface structure in titanium phthalocyanine sensors induced by the interaction with nitrogen oxides molecules. Generosi, A.; Paci, B.; Albertini, V. Rossi; Perfetti, P.; Paoletti, A. M.; Pennesi, G.; Rossi, G.; Caminiti, R. // Applied Physics Letters;10/31/2005, Vol. 87 Issue 18, p181904 

    Thin-film samples of titanium phthalocyanine, a sensor of environmental pollutants, were studied by time resolved energy-dispersive x-ray reflectivity (EDXR). This original method demonstrated to be an ideal tool to follow the evolution of the films morphology upon gas exposure, in situ, also...

  • Pure Bi4Ti3O12 thin films with improved ferroelectric properties. Chiou, Tai-Yi; Kuo, Dong-Hau // Applied Physics Letters;10/11/2004, Vol. 85 Issue 15, p3196 

    Pure Bi4Ti3O12 thin films with outstanding ferroelectric properties are reported. These films have been prepared by spin coating on substrates with a chemical solution. A (117)-preferred growth occurs at the annealing temperature of 600 °C. These films have a low coercive field of ∼35...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics