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本文采用PASCA技术研究铂在两种不同γ-Al_2O_3表面上的分散过程和状态。发现铂可与氧化铝表面上的S_k,S_(?)和S_t三类中心作用并生成稳定性和化学活性不同的复合物:PtO_xCI_y-S_k,PtO_xCl_y-S_(?)和PtO_xCl_y-S_t,并测定了o-Ps与这三种不同复合物之间的反应速度常数k。发现还原的催化剂表面上离子态(可溶性)铂含量NI与k值大小成正比。证明了不同氧化铝表面上的中心S(S_k、S(?)和S_t)在电化学性质上可能是不同的。还原过的Pt/Al_2O_3,催化剂是否存在着离子态铂主要取决于氧化铝本身的表面性质。
In this paper, the PASCA technique was used to study the dispersion process and state of platinum on two different γ-Al 2 O 3 surfaces. It was found that platinum can interact with three types of centers of S_k, S_ (?) And S_t on the surface of alumina and produce complexes with different stability and chemical activity: PtO_xCI_y-S_k, PtO_xCl_y-S_ (?) And PtO_xCl_y-S_t The reaction rate constant, k, between o-Ps and these three different complexes. It was found that the ionic state (soluble) content of Ni on the surface of the reduced catalyst is proportional to the value of k. It is demonstrated that the centers S (S_k, S (?) And S_t) on different alumina surfaces may be different in electrochemical properties. Reduced Pt / Al_2O_3, the existence of ionic platinum catalyst mainly depends on the surface properties of alumina itself.