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• The unique wounded CNTs were generated from the pyrolysis of the precursor without the addition of carbon sources. • The embedded Co 9 S 8 nanoparticle was obtained easily and required no further treatment or addition of metal sources. • This structure design strategy could be easily extended. • The Co 9 S 8 @NCNHP/S cathode exhibits the great electrochemical performance. [Display omitted] Lithium-sulfur (Li-S) battery is one of the most promising candidates for next-generation rechargeable batteries, while the volume expansion, severe shuttle effect, and sluggish reaction kinetics hinder its practical applications. Herein, a novel structure composed of Co 9 S 8 nanoparticles embedded in a N-doped carbon nanotube hollow polyhedron (Co 9 S 8 @NCNHP) is designed to address these issues. Co 9 S 8 nanoparticles can efficiently accelerate the kinetics of redox reaction and anchor the polysulfides, enhancing the electrochemical performance of cathodes. Furthermore, NCNHP can accommodate the huge volume expansion and block the diffusion of lithium polysulfides. Benefiting from this rational design, the Co 9 S 8 @NCNHP/S cathode exhibits a high initial discharge capacity of 1186 mAh·g−1 with a decay rate of 0.1% per cycle during 200 cycles at 0.2 C. An initial discharge capacity of 780 mAh·g−1 as well as a decay rate of 0.15% per cycle after 200 cycles can be obtained at a sulfur loading of 3.2 mg·cm−2. This strategy based on the combination of rational structure design and electrocatalysis could advance the cathode construction in Li-S batteries. [ABSTRACT FROM AUTHOR]

• A novel Ni 43 Mn 32 In 25 Heusler alloy film is deposited on Ni foam by PLD. • The activated NiMnIn/NF possesses overpotentials of 133.4 mV at a current density of –10 mA cm–2 for HER. • Electromagnet is used to realize the electrochemical measurement under in situ magnetic field. • Magnetic field promotes catalytic activity of NiMnIn/NF for HER. [Display omitted] Much effort has been devoted to developing novel electrodes of lower cost and higher efficiency to electrolyze water in scalable applications, which is mainly focused on 3d transition metals or oxides. In this work, Ni 43 Mn 32 In 25 (NiMnIn) Heusler alloy films with highly efficient hydrogen evolution reaction (HER) activity were deposited on porous Ni foam (NF) by pulsed laser deposition. With the synergetic contribution of constituent elements, the as-prepared NiMnIn films exhibited excellent performance with a low overpotential of 189.4 mV in the initial state and 133.4 mV after activation (at a current density of −10 mA cm−2) for HER in alkaline medium. Magnetic measurements have confirmed the ferromagnetic nature of NiMnIn films at room temperature, and the HER activity can be significantly improved by applying a magnetic field. The current density of NiMnIn/NF could be increased by 10% and 7% respectively, at a constant overpotential of 275 mV by applying a magnetic field of 8 kOe perpendicular and parallel to NF. This work suggests that Heusler alloys with various 3d transition metal constituents can be a potential efficient HER active electrode in water splitting, which has the magnetic field sensitivity for applications in magnetoelectrochemistry. [ABSTRACT FROM AUTHOR]