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It is of significant importance to suppress the polysulfide shuttle effect for the commercial application of lithiumâ€"sulfur batteries. Herein, continuous MIL-101(Cr) membranes were successfully fabricated on carbon nanotube films utilizing a simple in situ growth method, aiming at constructing interlayer materials for inhibiting the shuttle effect. Owing to the suitable pore aperture and super electrolyte wettability, the as-developed MIL-101(Cr) membrane can effectively inhibit the shuttle behaviour of polysulfides while allowing the fast transport of Li-ions simultaneously, working as an ionic sieve. Additionally, this MOFs membrane is also helpful in accelerating the polysulfide catalytic conversion. Therefore, the proposed interlayer delivers an extraordinary rate capability, showing a remarkable capacity of 661.9 mAh gâˆ'1 under 5 C. Meanwhile, it also exhibits a high initial capacity of 816.1 mAh gâˆ'1 at 1 C and an exceptional durability with an extremely low capacity fading of 0.046% per cycle over 500 cycles. [ABSTRACT FROM AUTHOR]

Developing efficient and durable electrocatalysts of oxygen reduction reaction (ORR) is critical for high‐performance air cathodes. Herein, a novel three‐dimensionally ordered macroporous oxygen‐deficient TiO2 framework embedded with N, P and Co‐tridoped carbon (3DOM Co/NPC@TiO2‐x) is elaborately designed for ORR. This unique structure offers a high surface area, good mass transfer, excellent electronic conductivity, and stability. Moreover, the experimental and theoretical studies reveal that the synergistic effect of N, P co‐doping and Co‐decoration is indispensable to promote the ORR performance, yielding high O2 adsorption energy and lowering the reaction barriers simultaneously. Accordingly, the ORR catalytic activity and stability of the proposed electrocatalyst are better than Pt/C in alkaline media. The resulting primary zinc‐air battery delivers a high open‐circuit voltage (1.50 V) and specific capacity (820 Wh kg−1) at 20 mA cm−2. This strategy, combining macroporous oxygen‐deficient oxide support with binary heteroatom doping, provides a new perspective for exploiting efficacious ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

Restraining the shuttle effect in lithium–sulfur (Li–S) battery is crucial to realize its practical application. In this work, a UiO-66@carbon (UiO-66@CC) interlayer was developed for Li–S battery by growing a continuous UiO-66 film on carbon cloth. The continuous UiO-66 crystal layer contributes to provide sufficient adsorptive and catalytic sites for efficient adsorption and catalytic conversion towards polysulfides. Moreover, the hydrophilic property of UiO-66 material ensures the full infiltration of electrolyte and accelerates the transportation of lithium ions. Profiting from the above advantages of the proposed interlayer, the shuttle effect is effectively inhibited and a fast redox kinetic is also realized. Accordingly, the Li–S battery using UiO-66@CC delivers a specific capacity of 1228.9 mAh g−1 at 0.2 C with a nearly 100% capacity retention after 100 cycles, and the first specific capacity is 1033.1 mAh g−1 at 1.0 C with a decay rate of 0.07% over 600 cycles. Meanwhile, UiO-66@CC interlayer also has an excellent rate performance with a specific capacity of 535.9 mAh g−1 at 5.0 C and a high area capacity of 6.2 mAh cm−2 at increased sulfur loading (8.15 mg cm−2). [ABSTRACT FROM AUTHOR]