A double microsecond-pulsed glow discharge ion source

A double pulsed glow discharge was compared to the single pulsed mode as an ion source for atomic mass spectrometry. During the time-window between the first applied voltage pulse and signal collection, the second pulse is applied. The double pulse was used to enhance analyte ionization and study the timing sequences within the pulsed glow discharge, the signals from which were followed using a time-of-flight mass spectrometer. Results showed that the double pulse glow discharge increased ion signals, provided that appropriate pulsing delays and gas flow rates were applied. The effect of the double pulse on methane-enhanced polyatomic cluster formation has also been evaluated.