Effect of low- temperature annealing on the optical and electrical properties of near-infrared photosensors based on colloidal quantum dots

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Published: Sep 21, 2026
DOI: https://doi.org/10.26629/uzjns.2026.07
Keywords:
colloidal PbSe nanocrystals, low-temperature annealing, near-infrared photosensors, PbSe nanocrystals

Main Article Content

Wafaa F Gebril
Department of Physics, Faculty of Sciences, University of Benghazi, Almarj, Libya
https://orcid.org/0000-0002-2113-1363

Abstract

The effect of low-temperature annealing on the electrical and optical properties of near-infrared photosensors based on colloidal PbSe nanocrystals capped with mercaptoacetic acid was investigated. The PbSe nanocrystals were synthesized via the hot-injection method, and their optical bandgap was determined to be approximately 0.78 eV from the optical absorbance spectrum. The electrical performance of the fabricated photosensors was evaluated by measuring their current–voltage (I–V) characteristics before and after annealing under nitrogen and air atmospheres. Additionally, the optical response of the devices was examined by measuring their spectral responsivity before and after air annealing. The PbSe nanocrystal device perfectly detected the near-infrared spectrum, and its performance was significantly improved after low-temperature air annealing. 60 °C air annealing enhanced the detectivity of the device by approximately 35% compared to its room-temperature detectivity.

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How to Cite
[1]
W. F. Gebril, “Effect of low- temperature annealing on the optical and electrical properties of near-infrared photosensors based on colloidal quantum dots”, UZJNS, vol. 3, no. 2, pp. 63–68, Sep. 2026.
Issue
Vol. 3 No. 2 (2026): Univ Zawia J Nat Sci
Section
Physics
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Author Biography

Wafaa F Gebril, Department of Physics, Faculty of Sciences, University of Benghazi, Almarj, Libya

Lecturer in the Department of Physics, Research background lies at the intersection of applied solid-state physics, nanostructured materials, optoelectronic device engineering, and possesses extensive experimental experience in cleanroom microfabrication, thin-film processing, nanomaterial synthesis, and device characterization. The primary research interests center on renewable energy technologies, with a strong focus on the numerical simulation, bandgap engineering, and parametric optimization of next-generation thin-film solar cell architectures.

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