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Chen et al. Microstructures 2023;3:2023025 https://dx.doi.org/10.20517/microstructures.2023.12 Page 9 of 31

Figure 5. Schematic illustrations of the formation process of (A) R-SMSI in Au/LDO. Reproduced with the permission of Ref. [60]
Copyright 2017, American Chemical Society, (B) R-SMSI in Au/MgO. Reproduced with the permission of Ref. [64] Copyright 2021,
Springer Nature, (C) L-SMSI in Pd/TiO . (D) TEM images of Pd/TiO . Reproduced with the permission of Ref. [65] Copyright 2021,
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2
American Chemical Society. (E) Schematic illustrations of the formation process of L-SMSI in Pt/CeO . (F) TEM images of Pt/CeO .
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Reproduced with the permission of Ref. [66] Copyright 2021, Springer Nature.
Laser-induced SMSI (L-SMSI)
Similar to the wcSMSI, L-SMSI also enables the migration of metastable supports to facilitate SMSI
formation without specific gaseous atmospheres and thermal treatment. Recently, Chen et al. successfully
constructed L-SMSI on a Pd/TiO catalyst by a photochemistry-driven methodology . Specifically, when
[65]
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excitation energy supplied by ultraviolet (UV) irradiation was greater than the band gap of titanium dioxide
(3.1 eV), the separated photoinduced reductive electrons (e ) and oxidative hole (H ) were generated to
+
-
3+
trigger the formation of Ti species/oxygen vacancies (O ) and then interfacial Pd-O -Ti sites, finally
3+
v
v
constructing the L-SMSI structures (as shown in Figure 5C and D). Subsequently, this as-constructed
L-SMSI layer is reversible between retraction on thermal O treatment and re-encapsulation on UV
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irradiation. Similarly, the L-SMSI strategy has been extended to CeO -supported Pt system catalysts and
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even to non-reducible oxide supports such as Al O and MgO. Zhang et al. applied an ultrafast laser to a
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2
Pt/CeO catalyst to boost the formation of surface defects and the migration of metastable CeO , and
x
2
succeeded in creating porous overlayers of CeO on Pt NPs (as shown in Figure 5E and F), which exhibit
x
superior catalytic activity and stability .
[66]
In summary, we briefly reviewed some typical strategies for constructing SMSI on various atmospheric
conditions, annealing temperatures, and oxide and non-oxide supports (as shown in Table 1). These new
types displayed similar properties to classical SMSI, including the electron and mass transfer between metal
NPs and substrates, the encapsulation of metal species by the migrating substrate, and the suppression of
the adsorption behavior of small molecules. Furthermore, they also exhibited remarkable strengths over