Pentacoordinate Al³⁺ Sites Anchoring Synthesis of Palladium Intermetallic Catalysts on Al₂O₃ Supports

Abstract

Size control of supported Pd-based intermetallic nanoparticles (i-NPs) remains a major challenge because the required high-temperature annealing for atomic diffusion and ordering easily causes metal sintering. Here, we described a pentacoordinate Al 3+ site (Al 3+ penta ) anchoring approach for the preparation of Pd-based i-NPs with controlled size, which takes advantage of the strong chemical interaction between Al 3+ penta sites and Pd-based i-NPs to realize size control. We synthesized six types of Pd-based i-NPs, and four of them can remain an average particle size of <6 nm. Furthermore, one of our prepared Pd-based i-NPs (that is, Pd 3 Pb) demonstrated outstanding performance in catalyzing the semihydrogenation of phenylacetylene.

Recent progress in intermetallic nanocrystals for electrocatalysis: From binary to ternary to high‐entropy intermetallics

“…Such a strong metal-support interaction can effectively immobilize the particles and prevent them from aggregation during high-temperature annealing, enabling the synthesis of size-controlled intermetallic nanoparticles. 72 S-or Ncontaining substrates are normally used for this purpose, due to the strong interactions between metals and S/N elements. 69,73 For example, S-doped carbon substrate was first prepared, onto which H 2 PtCl 6 and other metal salts were wet-impregnated.…”

“…Second, substrates having a strong interaction with the supported nanoparticles can be used. Such a strong metal‐support interaction can effectively immobilize the particles and prevent them from aggregation during high‐temperature annealing, enabling the synthesis of size‐controlled intermetallic nanoparticles 72 . S‐ or N‐containing substrates are normally used for this purpose, due to the strong interactions between metals and S/N elements 69,73 .…”

Tuning the Surface Wettability of Pd/COFs for Selective Hydrogenation

“…In general, the catalytic performance of metal NPs is greatly affected by their surface electronic and geometric structures, which could be tuned by size, morphology, foreign atom doping and the type of supports. [2][3][4][5][6][7] In addition to active sites, the surface wettability of supports also greatly affects the selectivity and activity of metal NPs by influencing the diffusion and adsorption of reactants, intermediates and products around the active sites. [8,9] More importantly, the enrichment of reactants near active sites is one of the unique properties of enzymes.…”

“…The development of highly selective and active metal catalysts has attracted great attention in the field of heterogeneous catalysis. In general, the catalytic performance of metal NPs is greatly affected by their surface electronic and geometric structures, which could be tuned by size, morphology, foreign atom doping and the type of supports [2–7] . In addition to active sites, the surface wettability of supports also greatly affects the selectivity and activity of metal NPs by influencing the diffusion and adsorption of reactants, intermediates and products around the active sites [8,9] .…”