Metal Oxide Nanostructures as Gas Sensing Devices

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2

Miniaturized Solid-State Gas Sensors

2.1 Gas Chromatography–Mass Spectrometry

The use of a mass spectrometer as the detector in gas chromatography was

developed in the 1950s by Gohlke and McLafferty [5,6]. This is a chemical

analysis instrument for separating gaseous species in a complex sample. The

system uses a ow-through narrow tube, known as the column, through

which different gaseous species of a test gas pass in a stream at different

rates depending on their various chemical and physical properties. As the

gaseous species exit at the end of the column, they are detected and identi-

ed electronically. The stationary phase in