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应用LRS、XRD、UV-DRS和TPR技术对负载氧化钨催化剂进行了表征.实验结果表明,WO_3在γ-Al_2O_3、TiO_2、SnO_2和ZrO_2载体表面高度分散直至形成完全覆盖单层;但在SiO_2表面WO_3难以分散.拉曼光谱是鉴别表面分散态和晶相WO_3的有力手段.对WO_3在表面单层覆盖的样品,表征表面 钨氧物种的拉曼振动频率的高低因载体而异.载体使表面钨氧物种稳定,抑制其还原并改变其还原进程.钨氧物种在载体表面的配位状态取决于负载量和载体的结晶结构.表面钨氧物种的拉曼频率和TPR还原峰温的高低与WO_3和载体之间相互作用的强弱有关.
The supported tungsten oxide catalysts were characterized by LRS, XRD, UV-DRS and TPR techniques. The experimental results show that WO 3 is highly dispersed on the surface of γ-Al 2 O 3, TiO 2, SnO 2 and ZrO 2 supports until the monolayers are completely covered. WO_3 is difficult to disperse.Raman spectroscopy is a powerful means to identify the surface dispersed state and the crystal phase WO_3 WO3 on the surface of the monolayer covered samples of surface tungsten oxygen species Raman vibration frequency of high and low carrier- Tungsten oxide species is stable, inhibit its reduction and change its reduction process.The coordination state of tungsten oxide species on the surface of the carrier depends on the loading and the crystal structure of the carrier.The Raman frequency of Tungsten oxide species and the peak height of TPR reduction with The interaction between WO_3 and the carrier is related to the strength.