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采用共沉淀－浸渍法在不同载体焙烧温度下，制备了不同Ａｌ／Ｂａ原子比的Ｐｔ／ＢａＡｌ２Ｏ４－Ａ１２Ｏ３系列样品。用ＸＲＤ，ＸＡＮＥＳ，ＥＸＡＦＳ，以及ＮＳＣ（ＮＯ_ｘ ｓｔｏｒａｇｅ ｃａｐａｃｉｔｙ）测定等手段对样品的微观结构和ＮＯ_ｘ储存性能进行了详细的表征．样品中Ｂａ物种是以ＢａＡｌ２Ｏ４和ＢａＣＯ３两种混合物相的形式存在，且伴随着载体焙烧温度和Ｂａ含量的降低，ＢａＡｌ２Ｏ４物相的分散度变高，ＮＯ_ｘ储存活性也随之提高，这表明ＢａＡｌ２Ｏ４相的分散度与样品的ＮＯ_ｘ储存性能密切相关，小颗粒的ＢａＡｌ２Ｏ４相是ＮＯ_ｘ的主要储存活性中心．在样品中，Ｐｔ物种以金属原子簇形式存在．分散度很高，其Ｐｔ—Ｐｔ壳层配位数较标样Ｐｔ粉有显著下降，Ｐｔ—Ｐｔ键长变短，出现了纳米收缩现象．高分散的小颗粒金属Ｐｔ原于簇为捕获和氧化ＮＯ_ｘ的主要活性中心．
Pt / BaAl2O4-A12O3 samples with different Al / Ba atomic ratios were prepared by coprecipitation-impregnation at different calcination temperatures. The microstructure and NO x storage performance of the samples were characterized in detail by means of XRD, XANES, EXAFS and NO_x storage capacity. The Ba species in the sample exists in the form of two mixture phases of BaAl2O4 and BaCO3. With the decrease of calcination temperature and Ba content, the dispersion of BaAl2O4 phase increases and the NO_x storage activity also increases, indicating that BaAl2O4 phase The dispersion degree is closely related to the NO_x storage performance of the sample, and the small particle BaAl2O4 phase is the main storage activity center of NO_x. In samples, Pt species exist as clusters of metal atoms. The dispersion degree is very high. The Pt-Pt shell coordination number is significantly lower than that of the standard Pt powder, and the Pt-Pt bond length is shortened, resulting in the phenomenon of nano-shrinkage. Highly dispersed small-particle metal Pt was originally found in clusters as the main active site for the capture and oxidation of NO x.