MOF-5 derived 3D ZnO/Ag micro-octahedra for ultrahigh response and selective triethylamine detection at low temperature.

The leakage of raw material triethylamine in the process of chemical production causes harm and damage to health and environment. Therefore, the development of triethylamine sensors with high response and selectivity is urgently needed. Using metal organic frames (MOF) as templates has become a new strategy to prepare nano structural metal oxides based gas sensing materials, which leads to a high specific surface area and enhanced gas sensing performances. In this work, the metal organic framework MOF-5 decorated with large Ag particles is prepared by a conventional one-step solvothermal method. Then 3D ZnO/Ag micro-octahedra assembled from ZnO nanosheets are derived by subsequent calcination. The 3D ZnO/Ag micro-octahedra based sensor exhibits excellent gas sensing performance toward triethylamine, including an ultrahigh response of 293.8–10 ppm and selectivity, as well as a low operating temperature of 200 °C, and long-time stability. The excellent triethylamine gas sensing performance can be attributed to the synergy effect between oxygen vacancies and the catalytic spillover effect generated by the noble metal silver. This work shows that MOF derived hierarchical 3D ZnO/Ag micro-octahedra provides a great potential for triethylamine monitoring. • A novel MOF template method is used for facile and large-scale synthesis of 3D ZnO/Ag micro-octahedra. • The 3D ZnO/Ag micro-octahedra shows an ultrahigh response and excellent selectivity to TEA. • Ag particles lead to noble metal catalytic spillover effect and form Schottky junctions with ZnO. [ABSTRACT FROM AUTHOR]