Preparation of Fe-doped NaBi(MoO4)2 nanorods and their improved gas-sensing properties

NaBi(MoO₄)₂ nanorods and nanoparticles were prepared by a facile solvothermal method with or without nitric acid. The crystal phase, morphology, and microstructure of the samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and the nitrogen adsorption isotherms. The NaBi(MoO₄)₂ nanorods and nanoparticles were tetragonal scheelite nanocrystals, and the nanorods were composed of 4–6 spheritic nanograins which were about 19 nm in diameter. The nanoparticles were aggregated randomly by 25 nm NaBi(MoO₄)₂ crystallites. Both NaBi(MoO₄)₂ nanorods and nanoparticles were mesopore structure. The sensors based on NaBi(MoO₄)₂ nanorods and nanoparticles exhibited high gas-sensing response (30.5 and 24.7) to 100 ppm n-butanol at optimal operating temperature of 370 °C.The composites of Fe-doped NaBi(MoO₄)₂ nanorods were prepared, and they showed better gas-sensing performances than pure NaBi(MoO₄)₂ nanorods due to promoting oxygen adsorption and catalysis by Fe doped. The highest sensitivity of the sensor based on 1 wt% Fe-doped NaBi(MoO₄)₂ nanorods was 48.4 to 100 ppm n-butanol at 300 °C.