Title: deep energy trap
Long Title: IUPAC Gold Book - deep energy trap
DOI: 10.1351/goldbook.14003
Status: current

Definition
Trap defined by an energy level (of trapped carriers) within the bandgap energy of a semiconductor or insulator with an energy difference between it and the conduction band (for electrons) or valence band (for holes) much greater than the energy of thermal excitation of the solid at a given temperature.

Notes
1) The dominant decay pathway of the trap is either by trapping of carriers of the opposite sign (see recombination centre) or by photoionisation (see colour centres).
2) Some active states of a photocatalytic centre are called a deep trap (as in solid-state physics).

Related Terms
- active states of a photocatalytic centre: https://goldbook.iupac.org//terms/view/13991
- colour centres: https://goldbook.iupac.org//terms/view/14002
- recombination centre: https://goldbook.iupac.org//terms/view/14081

Source
- PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 946 (https://doi.org/10.1351/PAC-REC-09-09-36)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14003/html
- json: https://goldbook.iupac.org/terms/view/14003/json
- xml: https://goldbook.iupac.org/terms/view/14003/xml

Citation: Citation: 'deep energy trap' 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.14003
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Accessed: 2026-05-31T05:19:43+00:00