Facile Synthesis of MOF-Derived Hierarchical Flower-Like Sr-Doped Co₃O₄ Structure for Effective TEA Sensing

Abstract

Metal-organic framework (MOF)-derived metal oxide semiconductors (MOSs) have drawn great attention because of their abundant pore structures, large surface area, and good gas accessibility. Herein, hierarchical flower-like Sr-doped cobalt oxide (Co3O4) structure is obtained utilizing MOF as a self-sacrificing template. Compared with undoped Co3O4, the 2 mol% Sr-doped Co3O4 shows better triethylamine (TEA) sensing performance. It exhibits not only high response values of 52 (the response of undoped Co3O4 are about 3.3) and short response/recovery time (40/58 s) to 100 ppm TEA at a low working temperature of 160 °C, but also excellent selectivity and long-term stability, which show that the as-obtained flower-like Sr-doped Co3O4 structure is an effective material to detect TEA gas. The enhanced sensing properties are attributed to the synergistic effect of the creation of more oxygen vacancies and larger surface area of flower-like structure.