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Strong metal-support interaction (SMSI) has been extensively studied in heterogeneous catalysis because of its significance in stabilizing active metals and tuning catalytic performance, but the origin of SMSI is not fully revealed. Herein, by using Pt/CeO 2 as a model catalyst, we report an embedding structure at the interface between Pt and (110) plane of CeO 2 , where Pt clusters (∼1.6 nm) are embedded into the lattice of ceria within 3-4 atomic layers. In contrast, this phenomenon is absent in the CeO 2 (100) support. This unique geometric structure, as an effective motivator, triggers more significant electron transfer from Pt clusters to CeO 2 (110) support accompanied by the formation of interfacial structure (Pt δ + -O v -Ce 3+ ), which plays a crucial role in stabilizing Pt nanoclusters. A comprehensive investigation based on experimental studies and theoretical calculations substantiates that the interfacial sites serve as the intrinsic active center toward water-gas shift reaction (WGSR), featuring a moderate strength CO activation adsorption and largely decreased energy barrier of H 2 O dissociation, accounting for the prominent catalytic activity of Pt/CeO 2 (110) (a reaction rate of 15.76 mol CO g Pt -1 h -1 and a turnover frequency value of 2.19 s -1 at 250 °C). In addition, the Pt/CeO 2 (110) catalyst shows a prominent durability within a 120 h time-on-stream test, far outperforming the Pt/CeO 2 (100) one, which demonstrates the advantages of this embedding structure for improving catalyst stability.

The atomically dispersed metal catalyst or single-atom catalyst (SAC) with the utmost metal utilization efficiency shows excellent selectivity toward ethylene compared to the metal nanoparticles catalyst in the acetylene semi-hydrogenation reaction. However, these catalysts normally work at relatively high temperatures. Achieving low-temperature reactivity while preserving high selectivity remains a challenge. To improve the intrinsic reactivity of SACs, rationally tailoring the coordination environments of the first metal atom by coordinating it with a second neighboring metal atom affords an opportunity. Here, we report the fabrication of a dual-atom catalyst (DAC) that features a bonded Pd 1 -Cu 1 atomic pair anchoring on nanodiamond graphene (ND@G). Compared to the single-atom Pd or Cu catalyst, it exhibits increased reactivity at a lower temperature, with 100% acetylene conversion and 92% ethylene selectivity at 110 °C. This work provides a strategy for designing DACs for low-temperature hydrogenation by manipulating the coordination environment of catalytic sites at the atomic level.