Slow Synthesis Methodology‐Directed Immiscible Octahedral Pd_xRh_1−x Dual‐Atom‐Site Catalysts for Superior Three‐Way Catalytic Activities over Rh

Abstract

This study provided an effective strategy to construct dual‐atom sites by solid–solution alloying. A slow synthesis methodology was established for the solid–solution preparations as dual‐atom‐site catalysts. The atomic‐level homogeneous PdxRh1−x dual‐atom‐site catalysts were successfully synthesized over the whole composition range, as evidenced by X‐ray powder diffraction and scanning transmission electron microscope energy‐dispersive X‐ray spectroscopy mapping measurements. The challenging morphology formation in the immiscible alloys was achieved by an energy‐controlling process as the octahedral Rh‐rich alloys. The Pd0.3Rh0.7 dual‐atom‐site catalyst had unique surface states to activate the key reactants of CO and NO in the complex three‐way catalytic reactions, and it performed significantly better than pure Rh.

High-throughput screening of multimetallic catalysts for three-way catalysis

“…Figure 6 compares the performance of the 51 MNPs when supported on γ-Al 2 O 3 at a fixed amount of loading (0.3 wt%) in terms of T50 of NO, CO, and C 3 H 6 . The best catalyst was found to be γ-Al 2 O 3 supported PdRh NPs, which is consistent with the previous research where PGMs were used for TWC 36,37 . In addition, Pd was found to be replaceable with Cu in the Rh-based bimetallic catalysts without a significant deterioration in activity.…”