This invention provides a
signal-enhanced pulsed
discharge helium ionization detector and detection method, comprising a sample introduction module and, from top to bottom, a grounding module, a
discharge region module, and a dual-biased
electrode ion focusing module. The grounding module includes a grounding
cathode needle.
Helium, serving as both the carrier gas and
discharge gas, enters the discharge region module from the grounding module. The grounding
cathode needle is used to ionize the
helium gas within the discharge region module to generate discharge material. The dual-biased
electrode ion focusing module includes a collecting
electrode and a first bias electrode and a second bias electrode coaxially disposed upstream and downstream of the collecting electrode. The second bias electrode provides a reverse
electric field to transport electrons flowing with the
helium gas to the collecting electrode. The sample introduction module, located below the dual-biased electrode
ion focusing module, is used to inject the standard gas sample to be detected countercurrently from the bottom into the dual-biased electrode ion focusing module to mix and ionize with the discharge material. This invention can significantly enhance the output
signal, improve sensitivity, and increase the
signal-to-
noise ratio.