Selective gas sensor

US5143696A · kind A · utility

Assignee

• Dornier GmbH · DE

Inventors

• Juergen Haas · Knittlingen, DE
• Carsten Plog · Markdorf, DE

Key dates

• Filing date: Oct 30, 1990
• Grant date: Sep 1, 1992
• Expiry date: Oct 30, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/221
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A sensor for selective determination of gases includes an electric capacitor having a gas permeable zeolite layer between 2 and 500 micrometer thick and being composed of a dielectric crystalline structure with a crystal size from 0.1 micrometer to 80 micrometer and having primary pores resulting in an internal surface from 100 to 1500 m.sup.2 /g, the diameter of the pores being between 0.1 and 1.5 nm which corresponds at least in order to magnitude to the kinetic diameter of the molecules of the gas to be detected, so that these molecules penetrate deep into the layer and its pores thereby changing the dielectric constant of the layer.