Ag nanoparticles-functionalized dumbbell-shaped In2O3 derived from MIL-68(In) with excellent sensitivity to formaldehyde

Formaldehyde, as a pollutant gas produced by indoor home decoration, threatens human health to Tablea large extent, so it is necessary to detect formaldehyde gas at low concentrations. The dumbbell-shaped indium oxide (In2O3) prepared with MIL-68(In) as the precursor was modified by Ag nanoparticles, and a series of characterization and analysis were performed on it. Field-emission scanning electronic microscope (FESEM) and transmission electron microscope (TEM) results showed that the Ag nanoparticles are successfully grown on the surface of In2O3. X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of Ag nanoparticles. The gas-sensing results showed that to 20 ppm formaldehyde, In2O3/Ag showed the highest response (29.9) at 160 °C, and the sensor showed high and rapid response-recovery, good reproducibility, and remarkable stability. This work proves that loading Ag is a feasible method to improve the performance of In2O3 based gas sensor.