【摘要】 <正> 近年来,Garten等针对Pt/TiO₂经氢气高温处理后的吸附特性,提出了金属和担体间强相互作用（SMSI）的概念.Horsley用X分子轨道法研究Pt/TiO₂体系,为P_t—Ti可能有键合的观点提供了一定的理论基础.根据热力学计算,也有人认为在高温下Pt/TiO₂能生成Pt₃Ti,但是缺少实验事实.更多还原

【Abstract】 Various samples of TiO2 support and Pt/TiO2 catalyst were studied by XRD before and after hydrogen or vacuum treatment at elevated temperatures. Pt metal and transition of TiO2 crystalline phases (anatase to rutile) were observed. After treating Pt/TiO2 in hydrogen above 850℃ or in vacuum at higher temperature, its XRD patterns denoting solid phases other than Pt metal and anatase or rutile were detected, they were identified as Pt3Ti and a modified titanium oxide solid phase deficient in oxygen. The appearance of Pt3Ti was found to be dependent on the post-treating condition and be related with the reducing state of TiO2. As a matter of fact, Pt3Ti vanished and reappeared when the catalyst samples were re-oxidized and reduced again at high temperatures. The appearance of Pt3Ti XRD pattern seems to be relevant to the strong metal support interaction on Pt/TiO2 catalyst.更多还原