Photoconductivity

Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation.[1]

When light is absorbed by a material such as a semiconductor, the number of free electrons and holes increases, resulting in increased electrical conductivity.[2] To cause excitation, the light that strikes the semiconductor must have enough energy to raise electrons across the band gap, or to excite the impurities within the band gap. When a bias voltage and a load resistor are used in series with the semiconductor, a voltage drop across the load resistors can be measured when the change in electrical conductivity of the material varies the current through the circuit.

Classic examples of photoconductive materials include:

Molecular photoconductors include organic,[6] inorganic,[7] and – more rarely – coordination compounds.[8][9]

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  3. ^ Pearsall, Thomas (2010). Photonics Essentials, 2nd edition. McGraw-Hill. ISBN 978-0-07-162935-5.
  4. ^ Law, Kock Yee (1993). "Organic photoconductive materials: recent trends and developments". Chemical Reviews. 93: 449–486. doi:10.1021/cr00017a020.
  5. ^ Belev, G.; Kasap, S. O. (2004-10-15). "Amorphous selenium as an X-ray photoconductor". Journal of Non-Crystalline Solids. Physics of Non-Crystalline Solids 10. 345–346: 484–488. Bibcode:2004JNCS..345..484B. doi:10.1016/j.jnoncrysol.2004.08.070. ISSN 0022-3093.
  6. ^ Weiss, David S.; Abkowitz, Martin (2010-01-13). "Advances in Organic Photoconductor Technology". Chemical Reviews. 110 (1): 479–526. doi:10.1021/cr900173r. ISSN 0009-2665. PMID 19848380.
  7. ^ Cai, Wensi; Li, Haiyun; Li, Mengchao; Wang, Meng; Wang, Huaxin; Chen, Jiangzhao; Zang, Zhigang (2021-05-13). "Opportunities and challenges of inorganic perovskites in high-performance photodetectors". Journal of Physics D: Applied Physics. 54 (29): 293002. Bibcode:2021JPhD...54C3002C. doi:10.1088/1361-6463/abf709. ISSN 0022-3727. S2CID 234883317.
  8. ^ Aragoni, M. Carla; Arca, Massimiliano; Devillanova, Francesco A.; Isaia, Francesco; Lippolis, Vito; Mancini, Annalisa; Pala, Luca; Verani, Gaetano; Agostinelli, Tiziano; Caironi, Mario; Natali, Dario (2007-02-01). "First example of a near-IR photodetector based on neutral [M(R-dmet)2] bis(1,2-dithiolene) metal complexes". Inorganic Chemistry Communications. 10 (2): 191–194. doi:10.1016/j.inoche.2006.10.019. ISSN 1387-7003.
  9. ^ Pintus, Anna; Ambrosio, Lucia; Aragoni, M. Carla; Binda, Maddalena; Coles, Simon J.; Hursthouse, Michael B.; Isaia, Francesco; Lippolis, Vito; Meloni, Giammarco; Natali, Dario; Orton, James B. (2020-05-04). "Photoconducting Devices with Response in the Visible–Near-Infrared Region Based on Neutral Ni Complexes of Aryl-1,2-dithiolene Ligands". Inorganic Chemistry. 59 (9): 6410–6421. doi:10.1021/acs.inorgchem.0c00491. hdl:11311/1146329. ISSN 0020-1669. PMID 32302124. S2CID 215809603.