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利用X-射线衍射研究了经氢还原及还原后又经高温水蒸气处理的PtSn／ZnAl2O4催化剂，结果表明，催化剂的相结构是Sn载量的函数．还原态的Pt／ZnAl2O4催化剂中Pt以金属态存在，Pt／Sn原子比为1：1、1：3及1：10的PtSn／ZnAl2O4催化剂还原后分别生成PtZn、PtSn、尽Sn及Pt物相；高温水蒸气处理对Pt／ZnAl2O4样品的相结构及Pt晶粒尺寸无明显影响，但却使Ptsn／ZnAl2O4催化剂的相结构发生显著变化；对于1：l及1：3的Ptsn／ZnAl2O4，水蒸气使各自还原态中的PtZn、PtSn合金重构为Pt3Sn合金，同时使1：10PtSn／ZnAl2O4的民β-Sn及Pt物相消失，而生成了新的PtSn合金相．
The XRD results of PtSn / ZnAl2O4 catalysts treated by hydrogen reduction and reduction with high temperature steam treatment show that the phase structure of the catalyst is a function of Sn loading. The Pt / ZnAl2O4 catalyst was reduced in the presence of Pt, Pt / ZnAl2O4 with Pt / Sn atomic ratio of 1: 1, 1:3 and 1:10, respectively, to form PtZn and PtSn, respectively. The phase structure of Pt / ZnAl2O4 and Pt grain size did not change obviously, but the phase structure of Ptsn / ZnAl2O4 catalyst changed significantly. The Ptsn / ZnAl2O4 with 1: 1 and 1: 3 Vapor recombination of PtZn and PtSn alloy in each reduction state into Pt3Sn alloy, while the disappearance of β-Sn and Pt phases in 1: 10PtSn / ZnAl2O4 and the formation of a new PtSn alloy phase.