Highly Stable Pt/CeO₂ Catalyst with Embedding Structure toward Water–Gas Shift Reaction

Abstract

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.

Schottky Barrier-Based Built-In Electric Field for Enhanced Tumor Photodynamic Therapy

“…46-1043) (Figure S6). When Pd NCs were combined with Co 3 O 4 , the intensity of Pd(200) and Co(400) significantly decreased, indicating that Co and Pd may be bonded by these two crystal planes with similar crystal plane spacing . Besides, uniform element distribution on Co 3 O 4 is visually observed (Figure S7), and the HRTEM image and elemental mappings of Co 3 O 4 @Pd further confirmed that Pd was successfully introduced into the Co 3 O 4 (Figure f and Figure S8).…”

Tuning the Metal–Support Interaction by Modulating CeO2 Oxygen Vacancies to Enhance the Toluene Oxidation Activity of Pt/CeO2 Catalysts

“…The 464 cm –1 Raman peak of CeO 2 with a fluorite structure represents a Ce–O bond stretching vibration ( F 2g ) mode. The 600 cm –1 peak indicates the defect induction mode ( D ), while the 1170 cm –1 peak is associated with the second order longitudinal optical mode (2LO) . The visible Raman spectra of the three catalysts exhibited slight differences.…”

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“…The excellent performance of the Cu/ZnO catalyst is generally attributed to the strong metal–support interaction (SMSI) effect, which may lead to the formation of specific active centres such as Cu δ + (0 < δ ≤ 1) or the stabilization of Cu 0 in a morphologically active form. 15–18 Chen et al 19–21 proposed that Cu δ + might play an essential role in the hydrogenation of DMM by facilitating the adsorption and activation of the carbonyl group. Zhang et al 22 reported that both Cu 0 and Cu + phases coexist on the surface of the Cu–Zn–Al catalyst, where Cu 0 and Cu + enable the formation of THF and GBL/BDO, respectively.…”