Triethylamine gas sensor based on Pt-functionalized hierarchical ZnO microspheres

Abstract Monitoring and detection of triethylamine (TEA) gas are indispensable to environmental and human safety. However, TEA gas sensor suffers from low response. Herein, unique nanosized-Pt-decorated hierarchical ZnO microspheres were prepared. Compared with pristine ZnO microspheres and Pt-c-ZnO (Pt nanoparticles deposited on commercial ZnO), the obtained Pt-ZnO exhibited the best TEA gas sensing behaviors, in terms of lower working temperature (200 °C), better selectivity and long-term stability. Notably, the response value of Pt-ZnO sensor towards 100 ppm TEA was up to 242, which was 50 and 16-fold higher than those of pristine ZnO and Pt-c-ZnO sensor, respectively. The superior properties were attributed to structural advantages as well as the synergistic effect between Pt and ZnO. The sensing mechanism was thoroughly clarified by the electron-sinker effect of Pt. It was further corroborated by Kelvin probe and density function theory (DFT) simulation. Moreover, higher surface adsorption oxygen activity and lower TEA adsorption energy of this optimal sample were demonstrated by temperature programmed desorption (O2-TPD) and DFT simulation. Based on the aforementioned advantages, Pt-ZnO becomes a satisfactory candidate for TEA gas sensors. Significantly, this work opens a new avenue for the understanding the mechanism for performance enhancement under.