Study on Oxygen-sensing Properties of La-Ni-O Composite Thin Films

摘要

The synthesis, gas-sensitivity and the influence of doping on physicochemical properties of La-Ni-O composite thin film were studied systematically. La-Ni-O composite thin films were formed by dip-coating method on the polycrystal Al_2O_3 ceramic substrates. The stable precursor solution was prepared using nitrate as raw materials and citric acid as chelating agent. The porous polycrystalline films were formed after calcining at 800℃ in reduction/oxidation atmosphere, the average grains size was about 100nm and the thickness was about 2μm for 8 dip-coating- heating-washing cycles. The La-Ni-O thin film was examined as a new kind of oxygen-sensing material. It had been shown that Ce doped La-Ni-O composite thin film had good response rating and reproducibility after long time exposure to the lean-burn/rich-burn atmosphere cycles.