物理化学学报 >> 1993, Vol. 9 >> Issue (04): 501-508.doi: 10.3866/PKU.WHXB19930415

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V2O5/TiO2催化剂活性组分与载体相互作用研究

叶代启; 梁红; 黄仲涛   

  1. 华南理工大学化学工程系，广州 510641
  • 收稿日期:1992-01-29 修回日期:1992-07-04 发布日期:1993-08-15
  • 通讯作者: 叶代启

Study on the Interaction Between the Active Phase and Support on V2O5/TiO2 Catalyst

Ye Dai-Qi; Liang Hong; Huang Zhong-Tao   

  1. Chemical Engineering Department, South-China University of Technology, Guangzhou 510641
  • Received:1992-01-29 Revised:1992-07-04 Published:1993-08-15
  • Contact: Ye Dai-Qi

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摘要： 制备了一系列负载型V-Ti-O催化剂, 运用现代分析测试手段如BET、TPD、NARP、XRD等进行表征. 研究发现负载于TiO_2上的V_2O_5由于相互作用而使其表面V=O物种选择外露, 载体TiO_2的晶体结构是决定它们之间相互作用的关键因素. 锐铁矿型TiO_2上获得最大V=O暴露的表面V_2O_5浓度显著低于金红石TiO_2载体上获得最大V=O暴露时的表面V_2O_5浓度. 而具有较大比表面及较强酸中心的TiO_2载体导致较强的相互作用. 即可获得较大的表面V=O暴露度.

关键词: V2O5, TiO2, 相互作用, 晶体结构

Abstract: V_2O_5 supported on various TiO_2 including anatase, rutile and mixture of both types have been investigated with various physicochemical measurements such as BET, TPD, NARP, XRD and so on. It has been found that the V=O species or the (010) plane of V_2O_5 on all the TiO_2 supports with large BET surface area are selectively exposed to the surface, though different modifications of TiO_2 results in different characteristics of exposure of (010) plane. For anatase, the maximum exposure of the V=O species is obtained at the surface concentration of V_2O_5 significantly lower than that for rutile. For the mixture, two maxima are obtained in the surface concentration of V_2O_5 corresponding to those for anatase and rutile respectively. Thus, it is concluded that crystal structure of the TiO_2 support determines the maximum exposure of (010) plane. The chemical activity of TiO_2 surface also seems to have an effect on the exposure of (010) plane. That is, the higher surface area and the stronger acidic property resulted in the high exposure of (010) plane.

Key words: V2O5, TiO2, Interaction, Crystal structure