Synthesis, Characterization and Gas Sensing Properties of Ag-doped α-Fe2O3 by Solid-state Grinding Method

Ag-doped α-Fe2O3 nanoparticles were synthesized by the solid-state grinding method, and the as-prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), thermogravimetry-differential thermal analysis (TG-DTA), and X-ray photoelectron spectroscopy (XPS) techniques. The analysis results indicated that all the particles were of spherical morphology and their size was about 10 nm. The gas sensing properties of the sensors based on the as-prepared Ag/Fe2O3 nanoparticles to different gas were investigated in detail. Compared the gas sensing test results of the Ag-doped α-Fe2O3 with the α-Fe2O3 without doped, all of the sensors based on the Ag-doped α-Fe2O3 nanoparticles possess much better sensing behavior than that of pure α-Fe2O3. The sensor based on the 300 °C-calcined 3%-Ag/Fe2O3 materials displayed the maximum response to H2S at 150 °C, and to ethanol at 245 °C. This solid-state grinding method prepared Ag/α-Fe2O3 nanomaterials are promising candidate for low temperature H2S detection.