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Title: Morphological variations as nonstandard test parameters for the response to pollutant gas concentration: An application to Ruthenium Phthalocyanine sensing films

Abstract

A systematic time-resolved energy dispersive x-ray reflectometry study was performed in situ on Ruthenium Phthalocyanine thin fims to estimate the morphological detection limits of this material as NO{sub 2} transducer and the influence of the gas concentration on the gas-film interaction mechanisms. The work validates the use of this unconventional method--based on the observation of the morphological parameters change--for evaluating the response of novel sensing materials in alternative to more standard procedures. Indeed, the morphological monitoring is shown to be sensitive to the gas concentration in a range comparable to the usual electroresistive measurements. Moreover, while the latter is only able to give the information on whether the gas is interacting with the sensor, the former is also able to discriminate among interaction processes of a different nature (in the present case the interaction limited to the film surface and the one involving the material bulk)

Authors:
; ; ; ; ; ; ;  [1];  [2];  [2]
  1. Istituto di Struttura della Materia-Area di Ricerca di Tor Vergata, Via del Fosso del Cavaliere 100, 00133 Rome (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
20778793
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 10; Other Information: DOI: 10.1063/1.2183817; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHEMICAL ANALYSIS; NITROGEN DIOXIDE; ORGANIC SEMICONDUCTORS; PHTHALOCYANINES; POLLUTANTS; RUTHENIUM COMPOUNDS; SENSITIVITY; THIN FILMS; TRANSDUCERS; X RADIATION

Citation Formats

Generosi, A., Paci, B., Albertini, V. Rossi, Perfetti, P., Paoletti, A.M., Pennesi, G., Rossi, G., Caminiti, R., Istituto di Struttura della Materia-Area di Ricerca di Montelibretti, Via Salaria Km.29.5, CP10 Monterotondo Stazione, Rome, and Dipartimento di Chimica, Universita 'La Sapienza' di Roma e sezione INFM, P.le A. Moro 5, 00185 Rome. Morphological variations as nonstandard test parameters for the response to pollutant gas concentration: An application to Ruthenium Phthalocyanine sensing films. United States: N. p., 2006. Web. doi:10.1063/1.2183817.
Generosi, A., Paci, B., Albertini, V. Rossi, Perfetti, P., Paoletti, A.M., Pennesi, G., Rossi, G., Caminiti, R., Istituto di Struttura della Materia-Area di Ricerca di Montelibretti, Via Salaria Km.29.5, CP10 Monterotondo Stazione, Rome, & Dipartimento di Chimica, Universita 'La Sapienza' di Roma e sezione INFM, P.le A. Moro 5, 00185 Rome. Morphological variations as nonstandard test parameters for the response to pollutant gas concentration: An application to Ruthenium Phthalocyanine sensing films. United States. doi:10.1063/1.2183817.
Generosi, A., Paci, B., Albertini, V. Rossi, Perfetti, P., Paoletti, A.M., Pennesi, G., Rossi, G., Caminiti, R., Istituto di Struttura della Materia-Area di Ricerca di Montelibretti, Via Salaria Km.29.5, CP10 Monterotondo Stazione, Rome, and Dipartimento di Chimica, Universita 'La Sapienza' di Roma e sezione INFM, P.le A. Moro 5, 00185 Rome. Mon . "Morphological variations as nonstandard test parameters for the response to pollutant gas concentration: An application to Ruthenium Phthalocyanine sensing films". United States. doi:10.1063/1.2183817.
@article{osti_20778793,
title = {Morphological variations as nonstandard test parameters for the response to pollutant gas concentration: An application to Ruthenium Phthalocyanine sensing films},
author = {Generosi, A. and Paci, B. and Albertini, V. Rossi and Perfetti, P. and Paoletti, A.M. and Pennesi, G. and Rossi, G. and Caminiti, R. and Istituto di Struttura della Materia-Area di Ricerca di Montelibretti, Via Salaria Km.29.5, CP10 Monterotondo Stazione, Rome and Dipartimento di Chimica, Universita 'La Sapienza' di Roma e sezione INFM, P.le A. Moro 5, 00185 Rome},
abstractNote = {A systematic time-resolved energy dispersive x-ray reflectometry study was performed in situ on Ruthenium Phthalocyanine thin fims to estimate the morphological detection limits of this material as NO{sub 2} transducer and the influence of the gas concentration on the gas-film interaction mechanisms. The work validates the use of this unconventional method--based on the observation of the morphological parameters change--for evaluating the response of novel sensing materials in alternative to more standard procedures. Indeed, the morphological monitoring is shown to be sensitive to the gas concentration in a range comparable to the usual electroresistive measurements. Moreover, while the latter is only able to give the information on whether the gas is interacting with the sensor, the former is also able to discriminate among interaction processes of a different nature (in the present case the interaction limited to the film surface and the one involving the material bulk)},
doi = {10.1063/1.2183817},
journal = {Applied Physics Letters},
number = 10,
volume = 88,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2006},
month = {Mon Mar 06 00:00:00 EST 2006}
}
  • Copper Phthalocyanine and other Metal Phthalocyanines are very flexible and tuned easily to modify their structural, spectroscopic, optical and electrical properties by either functionalizing them with various substituent groups or by replacing or adding a ligand to the central metal atom in the phthalocyanine ring and accordingly can be made sensitive and selective to various organic species or gaseous vapours. In the present work, we have dispersed Copper Phthalocyanine Salt (CuPcS) in sol-gel glass form using chemical route sol-gel method and studied its sensing mechanism with organic vapours like methanol and benzene and found that current increases onto their exposuremore » with vapours. A variation in the activation energies was also observed with exposure of vapours.« less
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  • Purpose: To improve the response of the microLion detector (PTW 31018) in small field conditions by optimizing the density of the detector's non-sensitive components using a novel method based on the detector's dose response function. Methods: The central values h(0,0) of the perturbation functions for the microLion detector and a volume of water equivalent to its sensitive volume were calculated using the Monte Carlo user code egs-chamber by scoring the dose absorbed by a 6 MV photon pencil beam incident on their centroids. Values of h(0,0) were plotted as a function of the density of the microLion's graphite electrode withmore » the detector placed in the axial orientation. The optimized density was found by finding the minimal value of h(0,0). Results: A density of 1.37 g/cm3 was found to minimize the perturbation function of the microLion detector. The modified microLion's response was then evaluated in small square fields with sides in the range of 5 – 40 mm and found to be consistent with highly watere-quivalent detectors such as a scintillating detector (Exradin W1) and a generic alanine detector in both axial and radial orientations. Conclusion: This work illustrates a novel method which can used to optimize the design of radiation detectors in small fields. This method should also work with other optimization parameters (e.g. thickness of electrode). Density-compensated detectors have the potential to eliminate the need to evaluate nonstandard field correction factors as described by the IAEA-AAPM formalism (Alfonso et al.) and simplify future dosimetry protocols for SRS/SBRT modalities. Finally, we also expect an improvement in the response of density-compensated detectors for composite IMRT fields.« less