Monodisperse PdCu@PtCu Core@Shell nanocrystal and their high activity and durability for oxygen reduction reaction

Intermetallic Compounds: Liquid-Phase Synthesis and Electrocatalytic Applications

Characterized by long-range atomic ordering, well-defined stoichiometry, and controlled crystal structure, intermetallics have attracted increasing attention in the area of chemical synthesis and catalytic applications. Liquid-phase synthesis of intermetallics has arisen as the promising methodology due to its precise control over size, shape, and resistance toward sintering compared with the traditional metallurgy. This short review tends to provide perspectives on the liquid-phase synthesis of intermetallics in terms of both thermodynamics and methodology, as well as its applications in various catalytic reactions. Specifically, basic thermodynamics and kinetics in the synthesis of intermetallics will be first discussed, followed by discussing the main factors that will affect the formation of intermetallics during synthesis. The application of intermetallics in electrocatalysis will be demonstrated case by case at last. We conclude the review with perspectives on the future developments with respect to both synthesis and catalytic applications.

Composition-driven shape evolution to Cu-rich PtCu octahedral alloy nanocrystals as superior bifunctional catalysts for methanol oxidation and oxygen reduction reaction

Synergetic effects between Pt and a cheap metal, downshift of the d-band center of Pt and the shape can boost the catalytic performance of Pt-based nanocrystals. Therefore, tailoring the shape and composition within the nanoscale is the key to designing a robust electrocatalyst in electrochemical energy conversion. Here, Cu-rich PtCu octahedral alloys achieved by a composition-driven shape evolution route have been used as outstanding bifunctional electrocatalysts for both methanol oxidation (MOR) and oxygen reduction reaction (ORR) in an acid medium. When benchmarked against commercial Pt black or Pt/C, for MOR, the specific activity/mass activity on Pt_34.5Cu_65.5 octahedra is 4.74/7.53 times higher than that on commercial Pt black; for ORR, the specific activity/mass activity on Pt_34.5Cu_65.5 octahedra is 7.7/4.2 times higher than that on commercial Pt/C. After a current-time test for 3600 s, the remaining mass activity on Pt_34.5Cu_65.5 octahedra is 35.5 times higher than that on commercial Pt black for MOR. After undergoing 5000 cycles for ORR, the remaining mass activity on Pt_34.5Cu_65.5 octahedra is 4.2 times higher than that on commercial Pt/C.