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[54]
Figure 4. (A) A-SMSI and Classical SMSI overlayer structure and behavior. Reproduced with the permission of Ref. . Copyright 2017,
Springer Nature. (B) Structural change of Cu/ZnO/Al O catalyst after different pretreatments and the corresponding elemental
2 3
distribution from transmission electron spectroscopy images. The DFT simulations over (C) Cu/ZnO/Al O . Reproduced with the
2 3
permission of Ref. [57] . Copyright 2022, Springer Nature. (D) Au @Ti/SiO model with two TiO atomic layers. Reproduced with the
x
55
2
permission of Ref. [58] . Copyright 2019, American Chemical Society.
Reaction-induced SMSI (R-SMSI) strategy is an effective method to induce the activation, migration, and
encapsulation of redox-inert support via its phase transition. For example, Wang et al. successfully achieved
R-SMSI between Au NPs and Mg-Al layered double oxides (LDO) vis a high-temperature treatment in
[60]
nitrogen atmosphere . The hydroxide-to-oxide support transformation is the prerequisite for the
construction of R-SMSI, and if Au NPs were loaded directly onto the LDO surface, the R-SMSI structure
was not obtainable under the same conditions (as shown in Figure 5A). Then, Dong et al. reported that the
cyclic change (MoC -to-MoO ) in the support of Au/MoC catalyst under a 20 vol% CH /He atmosphere
x
4
3
x
[61]
can realize R-SMSI . Later, they demonstrated that R-SMSI can also be achieved in the Ni/BN catalysts
[62]
under the same conditions due to the BN-to-BO interfacial change . In other studies, the support phase
x
change between BaCO -to-BaO of Co/BaO and Mn O -to-Mn O of Pt/Mn O catalysts were both formed
4
3
2
3
2
3
3
R-SMSI and exhibited excellent catalytic activity and stability [15,63] . Recently, a reversible reaction of
MgO+CO ↔ MgCO was employed to induce the R-SMSI of Au/MgO catalysts in a flowing CO
2
3
2
[64]
atmosphere (as shown in Figure 5B) . CO was applied to react with MgO support, and the MgCO was
2
3
subsequently decomposed into a regenerated MgO overlayer to encapsulate the Au NPs. Intriguingly, the
direct application of MgCO as a support is also able to realize the MgCO -to-MgO phase transition and to
3
3
construct a MgO overlayer on Au NPs. These studies demonstrate that the SMSI effect can also be
constructed on relatively redox-inert supports, and the mobility of the support after the phase change is
significantly higher than that of the original support, which also implies that the encapsulation rate of
metals by the R-SMSI strategy seems to be faster than that of classic SMSI.