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The design and synthesis of metallic nanocatalysts with distinct nanostructures and composition is still a noteworthy topic in the electrochemistry field. In this work, we have realized the morphological evolution of PdIr nanostructures in aqueous solution through the synergistic effect of self‐assembled functional surfactants and different halide ions, and achieved precise control of the kinetic and thermodynamic crystalline growth due to the different reduction potential between PdCl42−, PdBr42−, and PdI42−. The actual precursors of PdCl42− resulted in ultrathin nanodendrites, PdClxBr(4−x)2− for nanosheets and fewer branched nanodendrites, PdClxI(4−x)2− for nanorings, nanoflowers and multiply concave nanocubes. Owing to the synergistic advantages of structure and composition (alloyed Ir), PdIr nanodendrites exhibited enhanced electrocatalytic activity, anti‐poisoning ability, and stability toward alcohols (including ethanol, methanol, and glycerol) electrooxidation reactions. The results would be helpful for thoroughly understanding how structure‐directing surfactants and halide ions synergistically determine the production of advanced metallic nanocrystals. [ABSTRACT FROM AUTHOR]

In this work, a facile aqueous synthesis strategy was used (complete in 5 min at room temperature) to produce large‐size Pd, PdCu, and PdPtCu nanomeshes without additional organic ligands or solvent and the volume restriction of reaction solution. The obtained metallic nanomeshes possess graphene‐like morphology and a large size of dozens of microns. Abundant edges (coordinatively unsaturated sites, steps, and corners), defects (twins), and mesopores are seen in the metallic ultrathin structures. The formation mechanism for porous Pd nanomeshes disclosed that they undergo oriented attachment growth along the ⟨111⟩ direction. Owing to structural and compositional advantages, PdCu porous nanomeshes with certain elemental ratios (e. g. Pd87Cu13) presented enhanced electrocatalytic performance (larger mass activity, better CO tolerance and stability) toward ethanol oxidation. [ABSTRACT FROM AUTHOR]

Abstract: The ionothermal synthesis of extra‐large‐pore aluminophosphate zeotype with −CLO topological structure, DNL‐1, was studied by using 1,6‐hexanediamine and several quaternary ammonium compounds with different types of cations and anions as co‐structure‐directing agents (co‐SDAs). The phase selectivity and crystallization process were investigated, and results showed that the crystallization of the −CLO and LTA structures correlated with the alkalinity and concentration, rather than with the structure of the co‐SDA. By combining solid/solution 13C NMR spectroscopy and other characterizations on DNL‐1 obtained with different co‐SDAs, it was demonstrated that the ionic‐liquid cation was unalterably occluded in the structure, whereas occlusion of the co‐SDA cation was not imperative. A plausible crystallization pathway was accordingly deduced, in which alkaline co‐SDA, which acted as an acidity regulator in the ionothermal system, could facilitate the formation of the double‐four‐ring (d4r) unit (Al4P4O20), and influence their subsequent assembly mode around ionic‐liquid cations, and thus, direct the crystallization of −CLO and LTA structures at different concentrations of co‐SDA. [ABSTRACT FROM AUTHOR]