Fabrication H2S and NO2 Gas Sensors from Cu: GO Nano Films by Spin Coating Method

Abstract

Background

• Material: Copper-doped Graphene Oxide (Cu:GO) nanocomposite thin films.


• Technique: Spin coating, chosen for its speed, simplicity, and ability to produce uniform organic thin films on flat substrates.

Materials and Method

• Process Variable: Spin speed was systematically varied at 3000, 4000, 5000, 6000, and 7000 rpm (with corresponding variations in film weight/thickness).


• Target Gases: Hydrogen sulfide (H₂S) and nitrogen dioxide (NO₂).


• Testing Conditions: Constant operating temperatures ranging from 100°C to 200°C.

Results

A clear, inverse relationship was observed between operating temperature and gas sensitivity. Sensitivity diminished as temperature rose across the tested range (100-200°C).

• Effect on Sensor Kinetics: Increased operating temperature negatively impacted the sensor's dynamic performance:


• Increased Response Time: The sensor took longer to reach its maximum response upon gas exposur

Conclusions

The prepared Cu:GO nanomaterials demonstrate strong potential as effective gas sensors for H₂S and NO₂.· The spin coating method proves to be an excellent, scalable fabrication technique for creating a uniform sensing platform.· The operating temperature is a critical parameter that requires optimization, as it presents a trade-off: higher temperatures may improve reaction kinetics but, in this case, reduce overall sensitivity and recovery. This work provides a promising platform for sensitive and selective gas detection, with potential applications