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Título:
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Properties of polycrystalline gas sensors based on d.c. and a.c. electrical measurements
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Autores:
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Gutiérrez Monreal, Javier ;
Arés Escolar, Luis ;
Robla Villalba, José Ignacio ;
Horrillo Guemes, María Carmen ;
Sayago Olmo, Isabel ;
Agapito Serrano, Juan Andrés
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Tipo de documento:
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texto impreso
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Fecha de publicación:
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1992
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Dimensiones:
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application/pdf
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Nota general:
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info:eu-repo/semantics/openAccess
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Idiomas:
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Palabras clave:
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Estado = Publicado
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Materia = Ciencias: Física: Electrónica
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Tipo = Artículo
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Resumen:
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Electrical properties of polycrystalline gas sensors are analyzed by d.c. and a.c. measurements. d.c. electrical conductivity values compared with those obtained by admittance spectroscopy methods help to obtain a detailed 'on line' analysis of conductivity-modulated gas sensors. The electrical behaviour of grain boundaries is obtained and a new design of sensors can be achieved by enhancing the activity of surface states in the detecting operation. A Schottky barrier model is used to explain the grain boundary action under the presence of surrounding gases. The height of this barrier is a function of gas concentration due to the trapping of excess charge generated by gas adsorption at the interface. A comparison between this dependence, and a plot of the real and imaginary components of the admittance versus frequency at different gas concentrations, provides information on the different parameters that play a role in the conduction mechanisms. These methods have been applied to the design of a CO sensor based on tin oxide films for domestic purposes, the characteristics of which are presented.
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En línea:
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https://eprints.ucm.es/40639/1/Agapito-Properties-Polycrystaline.pdf
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