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制备了一系列Ｖ、Ａｇ、Ｎｉ原子比不同的三元氧化物，应用ＴＰＤ－ＭＳ技术研究了样品表面氧的性质，并测定了甲苯选择性氧化生成苯甲醛的催化活性．实验结果表明，样品表面存在有多种吸附的氧物种．在脱附温度＜９００℃：当Ｎｉ含量对Ａｇ（或Ｖ）的原子比为０．２５或０．５０时，仅在低温处出现有表面的Ｏ－和Ｏ２－两种氧物种的脱附峰；当Ｎｉ含量对Ａｇ（或Ｖ）的原子比增高到＞０．７５时，除有表面的Ｏ－和Ｏ２－两种氧物种的脱氧峰外，还有由于样品中的物相转变所生成的有晶格氧（Ｏ２－）参与脱附的脱氧峰．随着Ｖ－Ａｇ中Ｎｉ含量的改变，脱氧峰的脱附活化能Ｅｄ值也发生变化，３＃样品（Ｖ：Ａｇ：Ｎｉ＝１：１：０．７５）的Ｅｄ值最低，生成苯甲醛的选择性也最高．因此，样品的Ｅｄ值与生成苯甲醛的选择性之间存在着顺变关系．
A series of ternary oxides with different atomic ratios of V, Ag and Ni were prepared. The properties of oxygen on the surface of samples were studied by TPD-MS. The catalytic activity of selective oxidation of toluene to benzaldehyde was also measured. The experimental results show that there are many adsorbed oxygen species on the sample surface. At desorption temperature <900 ° C: when the atomic ratio of Ni content to Ag (or V) is 0.25 or 0.50, desorption of both surface O-and O 2 -x species occurs only at low temperatures Peak; when the atomic ratio of Ni to Ag (or V) is increased to> 0.75, in addition to the deoxygenation peaks of the surface O 2- and O 2- oxygen species, as well as the phase transition in the sample Generated lattice oxygen (O2-) involved in desorption deoxidation peak. With the change of Ni content in V-Ag, the value of Ed of the desorption activation energy of the deoxidation peak also changes. The Ed value of 3 # sample (V: Ag: Ni = 1: 1: 0.75) The highest selectivity. Therefore, there is a covarying relationship between the Ed value of the sample and the selectivity to benzaldehyde.