Title: specific photoadsorption number
Long Title: IUPAC Gold Book - specific photoadsorption number
DOI: 10.1351/goldbook.14090
Status: current

Definition
Maximum number of entities (molecules, atoms or radicals) adsorbed as a result of irradiation divided by the surface area and by the mass of adsorbent.

Note
This definition, per area and per mass, is misleading. It is included for historical reasons and was originally called specific photoadsorption capacity.

Related Term
- photoadsorption capacity: https://goldbook.iupac.org/terms/view/14034

Source
- PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 989 (https://doi.org/10.1351/PAC-REC-09-09-36)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14090/html
- json: https://goldbook.iupac.org/terms/view/14090/json
- xml: https://goldbook.iupac.org/terms/view/14090/xml

Citation: Citation: 'specific photoadsorption number' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.14090
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-08-10T01:32:28+00:00