The shuttling of soluble lithium polysulfides between the electrodes leads to serious capacity fading and excess use of electrolyte, which severely bottlenecks practical use of Li‐S batteries. Here, selective catalysis is proposed as a fundamental remedy for the consecutive solid‐liquid‐solid sulfur redox reactions. The proof‐of‐concept Indium (In)‐based catalyst targetedly decelerates the solid‐liquid conversion, dissolution of elemental sulfur to polysulfides, while accelerates the liquid‐solid conversion, deposition of polysulfides into insoluble Li2S, which basically reduces accumulation of polysulfides in electrolyte, finally inhibiting the shuttle effect. The selective catalysis is revealed, experimentally and theoretically, by changes of activation energies and kinetic currents, modified reaction pathway together with the probed dynamically changing catalyst (LiInS2 catalyst), and gradual deactivation of the In‐based catalyst. The In‐based battery works steadily over 1000 cycles at 4.0 C and yields an initial areal capacity up to 9.4 mAh cm−2 with a sulfur loading of ≈9.0 mg cm−2.

Understanding the catalytic mechanism of bimetallic nanocatalysts remains challenging. Here, we adopt an adsorbate mediated thermal reduction approach to yield monodispersed AuPd catalysts with continuous change of the Pd-Au coordination numbers embedded in a mesoporous carbonaceous matrix. The structure of nanoalloys is well-defined, allowing for a direct determination of the structure-property relationship. The results show that the Pd single atom and dimer are the active sites for the base-free oxidation of primary alcohols. Remarkably, the d -orbital charge on the surface of Pd serves as a descriptor to the adsorbate states and hence the catalytic performance. The maximum d -charge gain occurred in a composition with 33–50 at% Pd corresponds to up to 9 times enhancement in the reaction rate compared to the neat Pd. The findings not only open an avenue towards the rational design of catalysts but also enable the identification of key steps involved in the catalytic reactions.

Bimetallic Ni–Mo nitride nanotubes as highly active and stable bifunctional catalysts for full water splitting are favorably comparable to the performance of Pt/C and IrO2.

hydrogen fuel. To achieve high energy storage and conversion efficiencies, highperformance electrocatalysts are required. Precious metals such as Pt have shown high activity toward the hydrogen evolution reaction (HER) and the oxygen reduction reaction (ORR), while RuO 2 and IrO 2 have shown excellent activity toward the oxygen evolution reaction (OER). [1,2] Nevertheless, their high cost and low natural abundance have significantly limited the large-scale utilization of those precious electrocatalysts. Therefore, many efforts have been made to explore the nonprecious metal based electrocatalysts for full water splitting and metal-air batteries. Furthermore, to further reduce the cost for energy storage and conversion devices, it is highly desirable to develop trifunctional electrocatalysts that can catalyze the HER, ORR, and OER simultaneously in the same electrolyte.Recently, nonprecious transition-metal compound nanostructures with various morphologies have been reported for catalyzing the HER, OER, and/or ORR. Among these electrocatalysts, the nanotube (NT)-based ones with open ends and/ or porous features have attracted much interest because of their hollow interiors, porous characteristics, and large surface area, which greatly facilitate the exposure of active sites to the electrolyte, the quick diffusion of electrolyte into the active species, and the quick release of the thus-formed hydrogen and oxygen bubbles from the catalyst surface. Typically, tubular nanostructures, including Mo 2 C, [3,4] MoS 2 , [5,6] MoSe 2 , [7] Ni-Mo nitride, [8] Ni-Co selenide, [9] Ni-Co hydroxide, [10] Ni-Co nitride, [11] MoS 2 /SnO 2 , [12] and MoO x /MoS 2 [13] for catalyzing the HER, FeOOH/CeO 2 , [14] FeOOH/Co/FeOOH, [15] CoO x , [16] and Ni-Co phosphide [17] for catalyzing the OER, and Pt-Co/CN x , [18] PtAuCu, [19] Co@Co 3 O 4 /carbon nanotubes (CNTs), [20] CoSe 2 / CNTs, [21] NiCo/CNTs, [22] and Co x Mn 3−x O 4 , [23] for catalyzing the OER and ORR have been reported. Despite the advances in the transition-metal nanotube electrocatalysts for the HER, OER, and ORR, high-performance trifunctional electrocatalysts based on transition-metal nanotubes that can catalyze the HER, OER, and ORR simultaneously in the same electrolyte have rarely been reported.Besides controlling the morphology, tuning the electronic structure of the electrocatalysts through introducing heteroatoms into the catalyst host or designing multimetal catalysts has been considered as an important and efficient method for increasing the activities of electrocatalysts. [24][25][26][27][28][29] Among the multimetal catalysts mentioned above, Ni-Fe bimetal-based High-performance catalysts are required in various energy storage and conversion systems. In this work, hierarchical Ni-Fe-Mo trimetal nitride nanotubes (NTs) as highly efficient, low-cost, robustly stable, multifunctional catalysts through room-temperature Fe incorporation and subsequent thermal treatment for full water splitting and Zn-air batteries are fabricated. The two-electrode electrolyzer ...

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