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Inhibiting the shuttle effect of soluble polysulfides (LiPSs) is critical to lithium–sulfur (Li–S) batteries. Nevertheless, the conventional separator fails to block immigration of LiPSs between electrodes. Herein, the enriched oxygen vacancies were stabilized with ruthenium doping on niobium oxide/three-dimensional reduced graphene oxide nanosphere (Nb 2 O 5−x /Ru-3DG) to prepare a functional separator layer for LiPSs diffusion prevention. The inhibition mechanism is unraveled by density functional theoretical calculations and experimental results. Li–S batteries with Nb 2 O 5−x /Ru-3DG-based separator displayed an excellent capacity of 700.3 mAh g−1 with a long-term stability of 1000 cycles and a high rate-performance of 533.2 mAh g−1 at 8 C. An industrial-level pouch cell delivered an outstanding specific capacity of 925.8 mAh g−1 with an exceptional flexibility. This study could open a new strategy to design materials with controlled defects and doping for LiPSs immobilization, enhanced catalytic activities for redox reaction, and other catalysts for energy conversion and storage devices. [Display omitted] • The Nb 2 O 5−x /Ru-3DG was fabricated via a two-step strategy with facile hydrothermal and controlled annealing methods. • Ru doping immobilized O vacancies by compensating coordination number and modulating electronic properties. • The coated layer effectively entrapped polysulfide and accelerated reaction kinetics for Li-S batteries. • Assembled Nb 2 O 5−x /Ru-3DG-based batteries delivered an excellent rate capacity and a long cycling stability. [ABSTRACT FROM AUTHOR]

Water electrolysis is a remarkably advantageous technology for producing green hydrogen energy to substitute fossil fuels; however, the design of high-performance electrocatalysts with affordable prices and fast reaction kinetics is still a great challenge. Herein, we report well-dispersed ruthenium–ruthenium phosphide hetero-clusters stabilized vanadium carbide nanosheets (Ru−Ru 2 P/V 2 CT x) as an outstanding catalyst for pH−universal hydrogen evolution reaction. The Ru−Ru 2 P/V 2 CT x requires low overpotentials of 37, 21, and 95 mV to reach 10 mA·cm−2 in 0.5 M H 2 SO 4 , 1.0 M KOH, and 1.0 M PBS, respectively. Theoretical calculations well manifest the underlying structure–performance relationship of catalyst and mechanism for superb activity. The stack of anion exchange memalbrane water electrolyzer single cell achieves 1.0/2.0 A·cm−2 at 1.80/2.05 V at 60 °C, along with exceptional durability over 550 h continuous operation. These findings provide new insights into the development of efficient catalysts for water electrolyzers, ex. AEMWEs, in practical large-scale green hydrogen production. [Display omitted] • The cathodic catalyst of Ru−Ru 2 P hetero-clusters well dispersed V 2 CT x is prepared. • Synergistic effects result in low H 2 O dissociation energy barrier and optimum ΔG H*. • The catalyst can effectively promote the superior HER activity in a wide pH range. • The AEM stack of Ru−Ru 2 P/V 2 CT x shows cell voltage of 1.0/2.0 A·cm−2 at 1.80/2.05 V. • The AEM stack exhibits exceptional durability over 550 h continuous operation. [ABSTRACT FROM AUTHOR]

The rational design of the highly active, durable, and cost-effective catalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is essential for next-generation water splitting systems and zinc-air batteries. Herein, a novel strategy is demonstrated to design iron tin oxyselenide (Fe x Sn 1−x OSe) with enriched oxygen vacancies through a simple and straightforward hydrothermal and subsequent selenization process. The optimal Fe 0.33 Sn 0.67 OSe catalyst exhibits superior ORR, OER, and HER performances due to the numerous electroactive sites and high synergistic effects. The water electrolyzer requires a small voltage of 1.490 V and incredible reversibility over 24 h. Most interestingly, the Fe 0.33 Sn 0.67 OSe air-cathode based flexible ZAB exhibits a high power density of 153.96 mW cm−2 and ultralong cycle life for 400 h. This work opens a new strategy to establish highly active and durable multifunctional catalysts in next-generation energy conversion and storage systems. [Display omitted] • A novel 3D catalysts of iron tin oxyselenide grown on nickel foam is established. • The trifunctional catalyst exhibits excellent performance for OER, HER, and ORR. • Water splitting electrolyzer requires a small voltage of 1.49 V at 10 mA cm−2. • Zinc air battery delivers a peak power density of 153.96 mW cm−2, ultralong cycle-life for 400 h. [ABSTRACT FROM AUTHOR]