Development of SnO₂–AuNPs–GO-Modified Interdigitated Electrode Gas Sensors for Ethanol Detection

In this study, a specifically design nanocomposite known as tin oxide-gold nanoparticles-graphene oxide (SnO2–AuNPs–GO) was systemically synthesized using hydrothermal techniques before being incorporated onto the IDE electrode for the detection of ethanol gas. The prepared nanocomposite has excellent sensitivity and selectivity toward the ethanol gas and is able to detect the presence of analyte at low concentrations. In addition, SnO2–AuNPs–GO nanocomposite-based sensors produced are capable of differentiating the ethanol molecule in the presence of other harmful gases, such as ammonia and aldehyde. Besides, since the detection mechanism is operable at low temperatures, this sensory nanocomposite is able to reduce power consumption and improve the practical application of gas detection. The enhancement of the performance originates from the synergistic effects at the heterojunctions of SnO2, AuNPs, and GO for charge transport, which lead to response and recovery times for the sensor. Several characterization methods, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and field-emission scanning electron microscopy (FESEM) techniques, are used in investigating the interaction between SnO2, AuNPs, and GO molecules. In conclusion, the synthesized SnO2–AuNPs–GO composite-based sensor proposed has the potential to replace the present technology, such as Raman spectrum, electrochemical sensor, and amperometry biosensor in detecting ethanol gas as it has higher efficiency and is more cost-productive.