Term: photoionization detector
https://doi.org/10.1351/goldbook.P04621

Definition:
Radiation from an ultraviolet lamp ionizes certain species in the carrier gas. A potential difference is applied and the resulting ionization current is detected. The detector is only useful for substances with ionization potentials below about 11 eV. This makes it quite useful for detecting one component of a combined eluent when the other component, for instance nitrogen, has a high ionization potential. The detector has a small linear dynamic range and is capable of detecting substances below 1 ppmv.

Related Terms:
1) ultraviolet (http://doi.org/10.1351/goldbook.UT07492).
2) lamp (http://doi.org/10.1351/goldbook.L03447).
3) carrier gas (http://doi.org/10.1351/goldbook.C00863).
4) ionization (http://doi.org/10.1351/goldbook.I03183).
5) eluent (http://doi.org/10.1351/goldbook.E02040).
6) ionization potential (http://doi.org/10.1351/goldbook.I03208).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2191 (https://doi.org/10.1351/pac199062112167)

Citation: 'photoionization detector' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04621

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