丙烷氧化脱氢Ni-V-O催化剂的原位电导

In Situ Electrical Conductivity Study of Ni- V- O Catalysts Used in Oxidative Dehydrogenation of Propane

应用原位电导方法测定了Ni-V-O系列催化剂在氧＋丙烷→氧→丙烷连续变化气氛下的电导率,确定其导电类型并与其丙烷氧化脱氢制丙烯催化性能相关联.结果表明,p型半导体较n型半导体具有优良的催化氧化脱氢性能;在反应气氛下催化剂的p型半导性越大,n型半导性越小,其催化活性越高.这是由于p型半导体空穴导电,而n型半导体则为电子迁移导电,使得表面活性氧物种形成机理不同所致.

Electrical conductivity of Ni- V- O series catalysts was measured under different sequential gaseous atmospheres and at different temperatures, their conduction type was detemined and their catalytic behaviour in oxidative dehydrogenation of propane to propene was investigated.It was found that p- type semiconductor catalysts have a better catalytic behaviour than n- type ones.In reaction mixture,the higher the electrical conductivity of p- type semiconductor,the higher its catalytic activity,the lower electrical conductivity of n- type semiconductor,the higher its catalytic activity.These are due to different mechanism of the formation of the partial charged oxygen species on the surface of catalysts.