Nickel/Iron-Based Bimetallic MOFs derived nickel ferrite materials for triethylamine sensing performance

Nowadays, the metal-organic framework (MOF) based oxides have been gradually regarded as promising gas-sensing materials. In this study, the small-sized NiFe2O4 polyhedrons are synthesized at first through pyrolysis of bimetallic Fe/Ni-based bimetallic MOF precursors that synthesied by ligand acid complexation. Subsequently, a large-sized NFO polyhedrons with more stable morphology and structure were synthesized by changing the solvent composition. The concrete microstructure of the as-synthesized samples was characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and high-resolution transmission electron microscopy. The large-sized NFO polyhedrons based sensors present all-right triethylamine (TEA) gas sensing performances, such as fast response speed (6 s to 50 ppm TEA), enhanced response values (18.9 to 50 ppm TEA), good selectivity and repeatability at relatively low working temperature (190°C). Note that only few literatures have reported on the use of MOF-derived NFO materials in the TEA detection. Hence, our work expands the application fields of MOF-derived NFO materials. In addition, the sensing performances and sensing mechanism have been discussed in detail.