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采用一种新方法制备了V_2O_5样品片,并测定了它在各种驱气条件下的光谱变化,发现V=O双键在4OO——5O℃之间速度被活化,抽空时它放出晶格氧,V_2O_5分解.在V_2O_5表面找到有两种化学配位吸附水.一种是不受干扰的吸附水,它的V_(OH)带在3480Cm－1,一种是受到相邻V=O基干扰的吸附水，它有两个v_(oh)带，与V=O基成H键的V_(oh）为3400Cm-1,游离的V_(oh)是3620Cm-1.表面VOH基的频率在3700Cm-1.室温吸附的吡啶光谱批出，V_3O_2表面存在Lewis和Brφnsted两种酸点，Lewis酸点是那些配位水的吸附点，即配位数尚未饱和的表面V离子，Brφnsted酸点起源于VOH基。曝露于饱和水汽时，催化PVL变力一种吸附较弱的PYB但未发现两种酸点的转化。
V_2O_5 sample was prepared by a new method and its spectral change under various purging conditions was determined. It was found that the double bond V = O was activated at a temperature between 4 000 and 5 0 ° C, Oxygen and V_2O_5 decomposition.On the surface of V_2O_5, there are two chemisorbed adsorbed water, one is undisturbed adsorbed water whose V_ (OH) band is at 3480 cm-1 and one is affected by the adjacent V = O group Interference of adsorbed water, which has two v_ (oh) band, V_ (oh) with the V = O group H bond 3400Cm-1, free V_h is 3620Cm-1. The surface of the VOH group at a frequency of 3700Cm -1. The pyridine spectrum adsorbed at room temperature was awarded. There are Lewis acid sites and Brφnsted acid sites on the surface of V 3 O 2. The Lewis acid sites are the adsorption sites of coordination water, that is, the surface V ions of which coordination number is not saturated. Brφnsted acid sites originate from VOH group. When exposed to saturated water vapor, PVL catalysis catalyzed a weakly adsorbed PYB but no conversion of the two acid sites was found.