The electronic structure and grain size tuning of Sn/Ce co-modified ZnO for efficient triethylamine sensing at room temperature

Metal elements doping and the construction of heterojunction are commonly effective strategies to achieve the excellent gas sensing performance at room temperature (RT). This work realizes the detection of triethylamine (TEA) at RT under UV light by co-modifying ZnO with Sn and Ce, and the sensor based on ZSC-3 (2 at% Sn/0.7 at% Ce) exhibits optimal sensing properties to TEA with the responses of 11.5, fast response/recovery time of 18 s/137 s to 10 ppm TEA, and a low theoretical detection limit of 46 ppb. In the meantime, the sensor also possesses good selectivity, repeatability, and stability. Furthermore, the mechanism of sensor to TEA is discussed in the work, and the boosting properties are contributed to the synergistic effect of Sn and Ce by the adjustment of grain sizes, oxygen vacancies content, electron concentration, and even the separation of the photogenerated electron-hole pairs.