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

In this study, a specifically design nanocomposite known as SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>-AuNPs-GO (Tin Oxide-Gold Nanoparticles-Graphene Oxide) was systemically synthesised 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, SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>-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 SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>, AuNPs and GO for charge transport, which lead to response and recovery times for the sensor. Several characterisation methods such as FTIR, XRD, EDX, and FESEM techniques, are used in investigating the interaction between SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>, AuNPs, and GO molecules. In conclusion, the synthesised SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>-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.