We report a general concurrent template strategy for precise synthesis of mesoporous Pt‐/Pd‐based intermetallic nanoparticles with desired morphology and ordered mesostructure. The concurrent template not only supplies a mesoporous metal seed for re‐crystallization growth of atomically ordered intermetallic phases with unique atomic stoichiometry but also provides a nanoconfinement environment for nanocasting synthesis of mesoporous nanoparticles with ordered mesostructure and rhombic dodecahedral morphology under elevated temperature. Using the selective hydrogenation of 3‐nitrophenylacetylene as a proof‐of‐concept catalytic reaction, mesoporous intermetallic PtSn nanoparticles exhibited remarkably controllable intermetallic phase‐dependent catalytic selectivity and excellent catalytic stability. This work provides a very powerful strategy for precise preparation of ordered mesoporous intermetallic nanocrystals for application in selective catalysis and fuel cell electrocatalysis.

Mesoporous single crystals have unique potentials in catalysis, but remain unexplored owing to their grand synthetic challenge. Herein, we report a facile soft-template method to prepare palladium and palladium alloy nanocubes with single-crystallinity and abundant mesoporosity. The successful formation of these exotic nanostructures essentially relies on the co-introduction of cetyltrimethylammonium chloride as the surfactant template and extra Clions as the facet-selective capping agent under well controlled experimental conditions. Thanks to their large surface areas and penetrating mesoporous channels, our products exhibit great performances for electrochemical CO 2 reduction. The best sample from alloying palladium with copper enables the efficient formate production with high selectivity (90~100%) over a broad potential range, and great stability even under the working potential as cathodic as -0.5 V versus reversible hydrogen electrode. These performance metrics are far superior to previous Pd-based materials, and underscore the structural advantages of our products.

We reported mesoporosity engineering as a general strategy to promote semihydrogenation selectivity of palladium (Pd)‐based nanobundles catalysts. The best mesoporous PdP displayed full conversion, remarkable activity, excellent selectivity, and high stability in semihydrogenation of 1‐phenyl‐1‐propyne, all of which are remarkably better than commercial Lindlar catalysts. Mechanistic investigations ascribed high semihydrogenation selectivity to the continuous crystalline framework and penetrated mesoporous channel of catalysts that weakened the adsorption and interaction capacity of alkenes and thus inhibited over‐hydrogenation of alkenes to industrially unfavorable alkanes. Density functional theory calculations further demonstrated that convex crystalline mesoporosity of nanobundles catalysts electronically optimized the coordination environment of Pd active sites and energetically changed hydrogenation trends, resulting in a superior semihydrogenation selectivity to targeted alkenes.

Semi-hydrogenation of alkynes to industrially important alkenes is earnestly desirable in the fine chemical industry but energetically unfavorable. Herein, it is reported that mesoporous palladium (meso-Pd) catalyst changes the hydrogenation pathways in ethanol with ammonium borane as the hydrogen source, realizing the high catalytic selectivity of ≈99% in semi-hydrogenation of alkynes. Mechanism studies reveal that the active polar hydrogen can be produced and reserved well in the electron-rich mesoporous channels of meso-Pd catalyst, resulting in a transfer hydrogenation pathway, which selectively semi-hydrogenates alkynes into alkenes without over-hydrogenating alkenes into alkanes. Moreover, it is demonstrated that the polar hydrogen engineering of meso-Pd catalyst is highly efficient in various alkyne semihydrogenation and chemoselective hydrogenation reactions. The results thus establish metal catalyst mesostructuring as an alternative route for engineering polar hydrogen in the transfer hydrogenation reactions, thus realizing the high catalytic selectivity in various selective catalysis.

We reported mesoporosity engineering as a general strategy to promote semihydrogenation selectivity of palladium (Pd)‐based nanobundles catalysts. The best mesoporous PdP displayed full conversion, remarkable activity, excellent selectivity, and high stability in semihydrogenation of 1‐phenyl‐1‐propyne, all of which are remarkably better than commercial Lindlar catalysts. Mechanistic investigations ascribed high semihydrogenation selectivity to the continuous crystalline framework and penetrated mesoporous channel of catalysts that weakened the adsorption and interaction capacity of alkenes and thus inhibited over‐hydrogenation of alkenes to industrially unfavorable alkanes. Density functional theory calculations further demonstrated that convex crystalline mesoporosity of nanobundles catalysts electronically optimized the coordination environment of Pd active sites and energetically changed hydrogenation trends, resulting in a superior semihydrogenation selectivity to targeted alkenes.