Sn2+ doped NiO hollow nanofibers to improve triethylamine sensing characteristics through tuning oxygen defects

The triethylamine (TEA) sensors with high response and selective detection have been widely reported. However, sluggish kinetics of recovery process, high operating temperature, unsatisfied long-term stability and high detection limit still restrict their further application. In this work, NiO nanofibers with different contents of Sn2+ are prepared via electrospinning method. Gas sensing investigation indicates that the sensor based on 6 at% Sn2+ doped NiO nanofibers with an elevated baseline resistance exhibits the highest gas response and excellent recovery characteristic to TEA at 200 °C. The sensor shows a low detection limit at ppb level and good long-term stability within three months. In addition, the sensor only has a small variation on baseline resistance, gas response and response/recovery speed under different relative humidity. The promising gas sensing performance can be mainly attributed to the increase of the oxygen vacancies defects caused by the difference of Sn2+ and Ni2+, resistance changes and the hollow structure of as-prepared nanofibers.