Fe-doped NiO nanostructure-based gas sensor for selective detection of triethylamine and xylene

The real-time detection of noxious gases such as triethylamine (TEA) and xylene is important for human and environmental safety. In this work, Fe–NiO nanostructures with different doping concentrations were synthesized. By doping Fe, the gas sensitivity of NiO nanostructures was significantly improved. Gas-sensitive performance test results show that 0.93 at% Fe–NiO nanostructure-based sensors have more potential for TEA and xylene detection. The 0.93 at% Fe–NiO nanostructure-based sensor displays the highest response value of 38–50 ppm TEA at a working temperature of 220 °C and 18–50 ppm xylene at an operating temperature of 250 °C. Furthermore, the sensors show outstanding selectivity, stability and repeatability. The enhanced sensing characteristics can be ascribed to the doping of Fe with more oxygen vacancies. The as-prepared Fe–NiO nanostructures provide a novel dual-selectivity method for detection of TEA and xylene. In addition, the sensing mechanism was studied.