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用XPS技术研究了MZSM-5(M=Ga,Al,Fe)和不同类型Ga沸石的表面组成和电子结合能。研究结果表明,沸石的表面组成(Si/M)_s和电子结合能与构成沸石元素的种类和沸石的结构有关。在GaZSM-5、AlZSM-5、FeZSM-5三种沸石中,表相的与体相的Si/M值有如下关系:(Si/Al)_s<(Si/Al)_b,(Si/Ga)_s或(Si/Fe)_s>(Si/Ga)_b或(Si/Al)_b。在几种Ga沸石中,主要分为两类:一类为(Si/Ga)_s近似等于(Si/Ga)_b,如方钠石(sodalite)和Y型沸石;另一类为(Si/Ga)_s高于(Si/Ga)_b,如L、Ω、菱钾沸石(offretite)、ZSM-5型沸石。
The surface composition and electron binding energy of MZSM-5 (M = Ga, Al, Fe) and different types of zeolite Ga were studied by XPS technique. The results show that the surface composition of the zeolite (Si / M) _s and the electron binding energy are related to the types of zeolite elements and the structure of the zeolite. Among the three zeolites GaZSM-5, AlZSM-5 and FeZSM-5, the Si / M values of the bulk phase and the bulk phase have the following relationships: (Si / Al) _s <(Si / Al) ) _s or (Si / Fe) _s> (Si / Ga) _b or (Si / Al) _b. Among the several Ga zeolites, there are mainly two types: one is (Si / Ga) _s approximately equal to (Si / Ga) _b such as sodalite and Y zeolite; the other is (Si / Ga) _s is higher than (Si / Ga) _b, such as L, Ω, offretite, ZSM-5 type zeolite.