Robust response to NO2 gas on SnO2 heater/CNT gas sensor structures

Abstract

Nitrogen dioxide (NO2) is a harmful air pollutant, which is primarily emitted from vehicle exhausts and industrial processes, and it poses significant health risks. This study presents a reliable solution for the detection of NO₂ by integrating a transparent carbon nanotube (CNT) gas sensor with an SnO2-based memristor heater (MH). First, the heating capabilities and gas sensitivity of the SnO2-based MH are evaluated at varying thicknesses (100–200 nm) to optimize performance. The findings of the study indicate that the 175 nm SnO2-based MH exhibited the highest sensitivity, which included a 40.69 % response at 20 ppm and a 19.42 % response at 0.5 ppm. Furthermore, SnO2 demonstrates superior thermal stability and reduced variability compared to conventional ZnO-based MH, which guarantees a consistent performance for 50 cycles. These results underscore the potential of SnO2-based MH for next-generation gas sensors, which provide improved sensitivity, durability, and reliability for industrial safety applications.