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HomeEngineering ChemistryEngineering Chemistry Vol. 13Enhanced Humidity Sensing Properties of Sn-Doped...

Enhanced Humidity Sensing Properties of Sn-Doped ZnO Nanostructures on AZO/PET Substrates via Sol-Gel Immersion Method

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Abstract:

This work reports the structural and humidity-sensing properties of Tin (Sn)-doped Zinc Oxide (ZnO) nanostructures deposited on Aluminum-doped Zinc Oxide/Polyethylene Terephthalate (AZO/PET) substrates via the sol-gel immersion method. Accordingly, X-ray Diffraction (XRD) and FESEM analyses confirmed that low-level Sn incorporation (1 at.%) enhanced the (002) orientation and crystallinity, while higher doping introduced lattice distortion and defects. Meanwhile, humidity sensing measurements revealed that undoped ZnO exhibited the highest sensitivity (178.5), though it recorded a very slow response (231 s) and recovery (648 s). In contrast, 1 at.% Sn-doped ZnO achieved a balanced performance, combining high sensitivity (144.4) with much faster response (121 s) and recovery (411 s). These results demonstrate that controlled Sn doping optimizes ZnO nanostructures for flexible humidity-sensing applications. Overall, the findings provide valuable insight for developing real-time environmental and wearable sensing devices, with future work focusing on stability testing and mechanical flexibility evaluation.

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Engineering Chemistry Vol. 13

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Periodical:

Engineering Chemistry (Volume 13)

Pages:

39-50

DOI:

https://doi.org/10.4028/p-9bwDd3

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Online since:

February 2026

Authors:

Shahirah Ahmad Kamal, Nor Diyana Md. Sin*, Mohamad Hafiz Mamat, Mohamad Zhafran Hussin, Fatimah Khairiah Abd Hamid, Mohd Hanapiah Abdullah, Noor Asnida Asli

Keywords:

Doped ZnO, Flexible Sensor, Humidity Sensor, Low Temperature Synthesis, Nanostructure Thin Film

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* - Corresponding Author

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