Ammonia sensor for opto chemical detection of ammonia in gases, has sensor layer annealed at preset ranges, where inorganic or organic crystalline substances are soluble in sol of gel in sensor layer

摘要

The sensor has an optical selection unit directed toward a sensor layer, where the sensor layer consists of a silicon dioxide gel or a silicon dioxide-containing mixture gel with a sol. An ammonia-sensitive indicator is provided comprising bromocresol green, bromocresol magenta, bromothymol blue, bromoxylenol blue and/or methyl red. Inorganic or organic crystalline substances e.g. ammonium hydrogen carbonate, ammonium carbonate, ammonium carbamate and carbonic acid diamide, are soluble in the sol. The sensor layer is annealed at 120 degree Celsius to 140 degree Celsius. The sensor layer is deposited on a planar support, light guide, cuvette, cylinder or a tube made of transparent glass or polymer or on a paper. An independent claim is also included for a method for manufacturing a sensor layer for an ammonia sensor.