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Rational design of metal oxide supported non-precious metals is essential for the development of stable and high-efficiency oxygen reduction reaction (ORR) electrocatalysts. Here, an efficient ORR catalyst consisting of binary Fe/Co nanoclusters supported by defective tungsten oxide and embedded N-doped carbon layer (NC) with a 3D ordered macroporous architecture (3DOM Fe/Co@NC-WO 2−x ) is developed. The oxygen deficient 3DOM WO 2−x not only serves as a porous and stable support, but also enhances the conductivity and ensures good dispersion of the binary Fe/Co nanocluster, benefiting its ORR catalytic activity. Theoretical calculation shows that there exists a synergistic effect of electron transfer from Fe to Co in the supported binary Fe/Co cluster, promoting the ORR reaction energetics. Accordingly, the 3DOM Fe/Co@NC-WO 2−x catalyst exhibits excellent ORR activity in alkaline medium with a half wave potential (E 1/2 ) of 0.87 V higher than that of Pt/C (0.85 V). The zinc-air batteries assembled by 3DOM Fe/Co@NC-WO 2−x cathode deliver a higher power density and specific capacity than that of Pt/C. A new strategy of combining synergistic binary-metal nanoclusters and conductive metal oxide support design is provided here to develop efficient and durable ORR electrocatalyst.

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Metal phosphorus trichalcogenides (MPTCs) are structurally adjustable 2D layered materials with unique electronic structures and high chemical diversity, implying the huge potential for energy storage application. In the typical electrochemical reaction process, rapid electron/ion conduction and abundant ion transport channels are the key parameters that influence the overall electrochemical performance of the electrode materials. Herein, 2D Cd 1−x PS 3 Li 2x nanosheets with enhanced mixed electronic/ionic conductivity are synthesized by the intercalation and vacancy strategy. The as-prepared thin-layered Cd 1−x PS 3 Li 2x electrode delivers high capacities of 1056 mAh g −1 at 0.2 A g −1 and 678 mAh g −1 at 8 A g −1 , when used as anode in lithium-ion batteries. The variation of electronic structure and spatial layered structure in Cd 1−x PS 3 Li 2x induced by the synergistic effect of lithium-ion intercalation and Cd vacancies promote the dynamics of mixed electron/ion transport and offer more ion diffusion pathways, resulting in its excellent electrochemical performance. The strategy of mixed electron/ion conduction tuning for Cd 1−x PS 3 Li 2x can be extended to other MPTCs compounds to further develop their potential in the field of energy storage.

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