The synthesis of atomically ordered Pt-based intermetallic electrocatalysts for the direct alcohol fuel cells generally requires the addition of surfactants or the high-temperature annealing. However, some residual surfactants on the surface of the as-synthesized catalysts would prevent the exposure of catalytic active sites, and the high-temperature annealing process is easy to accelerate the sintering of the metal, which both lead to the decline of electrocatalytic performance. Herein, we construct the atomically ordered bimetallic PtBi intermetallics with clean surfaces and unique three-dimensional hollow acorn-shell-like structure (3D PtBi HASL) by a simple, low-temperature, and surfactant-free one-pot synthetic approach. Benefiting from the special hollow structures, the obtained 3D PtBi HASL intermetallics expose abundant accessible active sites. Moreover, the introduction of oxophilic metal Bi can enhance adsorption of OH_ads, thereby significantly facilitating removal of poisoned intermediates. Density functional theory (DFT) simulations further indicate that formation of the PtBi intermetallic phase with the downshift of the Pt d-band center endows 3D Pt_49.4Bi_50.6 HASL intermetallics with significantly attenuated CO_ads and enhanced OH_ads adsorption, bringing about the boosting electrocatalytic property. The mass activity of the 3D Pt_49.4Bi_50.6 HASL intermetallics for ethylene glycol oxidation reaction is as high as 24.67 A·mg_Pt⁻¹, which is 12.98 times higher than that of commercial Pt/C (1.90 A·mg_Pt⁻¹). This work may inspire the design of Pt-based intermetallics as high-efficiency anode electrocatalysts for fuel cell applications.

In catalysis, tuning the structural composition of the metal alloy is known as an efficient way to optimize the catalytic activity. This work presents the synthesis of compositional segregated six-armed PtCu nanostars via a facile solvothermal method and their distinct composition-structure-dependent performances in electrooxidation processes. The alloy is shown to have a unique six arms with a Cu-rich dodecahedral core, mainly composed of {110} facets and exhibit superior catalytic activity toward alcohols electrooxidation compared to the hollow counterpart where Cu was selectively etched. Density functional theory (DFT) calculations suggest that the formation of hydroxyl intermediate (OH*) is crucial to detoxify CO poisoning during the electrooxidation processes. The addition of Cu is found to effectively adjust the d band location of the alloy catalyst and thus enhance the formation of *OH intermediate from water splitting, which decreases the coverage of *CO intermediate. Our work demonstrates that the unique compositional anisotropy in alloy catalyst may boost their applications in electrocatalysis and provides a methodology for the design of this type catalyst.

A simple and efficient solution-based method for the synthesis of Pd-Ni bimetallic nanoparticles (NPs) has been developed. A series of Pd-Ni bimetallic NPs were readily achieved by reduction of PdCl₂ and Ni(acac)₂ (acac = acetylacetonate) in the presence of oleylamine (OAm), oleic acid (OA) and benzyl alcohol. Furthermore, by using high-resolution transmission electron microscopy (HRTEM), energy-dispersive spectrometry (EDS) mapping and X-ray diffraction (XRD), we demonstrate that the as-prepared Pd-Ni bimetallic NPs have core-shell structures with a Pd-rich core and a Ni-rich shell. In addition, the as-obtained Pd-Ni bimetallic NPs with varying compositions show excellent catalytic activities in the Miyaura-Suzuki reaction. When the nickel molar percentage was 0.23 to 0.65, the conversion with the as-obtained Pd-Ni bimetallic catalysts was above 90%. It is believed that this strategy can be employed to produce a variety of other well-defined core-shell type multimetallic nanostructures.