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TiO2中体相还原态与气敏性质之间的关系已有理论预测但一直未得到实验验证.在此,我们报道一种利用多孔无定型二氧化钛作前驱体制备含热稳定体相还原态TiO2的化学方法.紫外-可见漫反射光谱,电子顺磁共振波谱(EPR)以及X-射线光电子能谱(XPS)证明所获材料中含有的体相还原态为热稳定的Ti3+离子以及捕获电子的氧缺位.O2-程序升温脱附测量结果表明,体相还原态的存在可以显著提升二氧化钛表面对氧分子的吸附作用.所获得的体相还原纳米材料不仅表现出优越的对有机分子(乙醇、甲醇及丙酮)的传感性和快速响应性,而且具有对CO传感的良好选择性(相对于CH4和H2).测试结果证实了TiO2传感材料中体相还原态的重要性,材料的气体传感性能与TiO2表面氧气分子吸附作用密切相关.
The relationship between the phase reduction and the gas-sensing properties of TiO2 has been theoretically predicted but has not been experimentally verified here, and we report here a novel method for preparing TiO2 with reduced-phase heat-stable phase using porous amorphous titanium dioxide as a precursor Chemical methods UV-Vis diffuse reflectance spectroscopy, electron paramagnetic resonance spectroscopy (EPR) and X-ray photoelectron spectroscopy (XPS) proved that the obtained material contained the phase-reduced Ti3 + ions and electron- Absence of vacancies.The measurement results of temperature-programmed desorption by O2-process show that the existence of bulk phase reduction can significantly enhance the adsorption of oxygen molecules on the surface of titania.The obtained bulk reduced nanomaterials not only show superior performance for organic molecules (ethanol, Methanol and acetone) and has good selectivity for CO sensing (relative to CH4 and H2) .The test results confirm the importance of the bulk phase reduction in TiO2 sensing materials, The gas sensing performance is closely related to the molecular oxygen adsorption on TiO2 surface.