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Highly distributed Pd NPs supported on the surface of sulfonic acid functionalized metal organic frameworks (MIL-101-SO3H) were synthesized via a simple thermal decomposition method. The as-synthesized Pd/MIL-101-SO3H was used to catalyze a hydrogenation/esterification cascade reaction for the conversion of biomass derivatives (furoic acid) into high value chemicals (ethyl tetrahydro-2-furoate). [ABSTRACT FROM AUTHOR]

Rational synthesis of bimetallic alloy nanocrystals (NCs) is still a great challenge. Especially, spatially uniform alloy NCs are very difficult to achieve because of the different reduction rates of the individual alloy components. Herein we propose a facile wet chemical synthetic strategy to prepare uniform bimetallic alloy NCs with tunable composition by controlling the growth of alloy NCs under diffusion controlled conditions. Using this strategy, we successfully synthesized trisoctahedral (TOH) Au-Pd alloy NCs enclosed by { hhl} high-index facets with uniform spatial distributions and different compositions. Significantly, using our strategy, the composition of the as-prepared Au-Pd alloy NCs is identical to the ratio of the two metal precursors in the reaction solution over a wide range. Investigation of the composition-dependent electrochemical behavior of the as-prepared TOH Au-Pd alloy NCs showed that the TOH Au-Pd alloy NCs containing 14.1 atom% Pd exhibited the best activity. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Graphical abstract During the seed-mediated growth, the structure of formed Pd-Au nano-heterostructure can be either centrosymmetric Pd@Au core-shell trisoctahedra or asymmetric Pd-Au hetero-dimers. What does play a key role for the symmetry breaking of bimetal nano-heterostructures? Abstract Seed-mediated growth is the most general way to controllably synthesize bimetal nano-heterostructures. Despite successful instances through trial and error were reported, the way for second metal depositing on the seed, namely whether the symmetry of resulted nano-heterostructure follows the original crystal symmetry of seed metal, remains an unpredictable issue to date. In this work, we propose that the thermodynamic factor, i.e., the difference of equilibrium electrochemical potentials (corresponding to their Fermi levels) of two metals in the growth solution, plays a key role for the symmetry breaking of bimetal nano-heterostructures during the seed-mediated growth. As a proof-of-principle experiment, by reversing the relative position of Fermi levels of the Pd nanocube seeds and the second metal Au with changing the concentration of reductant (L-ascorbic acid) in the growth solution, the structure of as-prepared products successfully evolved from centrosymmetric Pd@Au core-shell trisoctahedra to asymmetric Pd-Au hetero-dimers. The idea was further demonstrated by the growth of Ag on the Pd seeds. The present work intends to reveal the origin of symmetry breaking in the seed-mediated growth of nano-heterostructures from the viewpoint of thermodynamics, and these new insights will in turn help to achieve rational construction of bimetal nano-heterostructures with specific functions. [ABSTRACT FROM AUTHOR]