MWCNT-based material as a gas sensor for H2S and NO2, synthesise and characterisation

[Display omitted] •A novel method used to prepare fullerene from waste oil.•Fullerene was evaluated as gas sensors for H2S and NO2 gases. In this study, waste oil was used to produce multi-walled carbon nanotubes (MWCNTs). TEM, FE-SEM and AFM techniques were used to characterise MWCNTs. In addition, the sizes of the synthesised MWCNTs ranged from 28.3 to 49.51 nm. The FTIR technique was used to prove the production of MWCNTCOO. The produced MWCNTCOO were evaluated as gas sensors for H2S and NO2 gases at various temperatures and time intervals. The higher H2S sensitivity response was recorded at 70 °C, with a response of 10.6, meanwhile, the greater NO2 sensitivity response was observed at 190 °C, with a response of 29.9. At 25 °C, the response and recovery times for 100 ppm H2S gas were 18.9 and 96.3 s, respectively, whereas, at 100 °C, they were 28.8 and 85.5 s, respectively, thereby demonstrating that the sensor has unique response recovery features.