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Development of highly efficient and stable non-precious metal-based pH-universal catalysts for hydrogen evolution reaction (HER) at high current densities remains challenging for water electrolysis-based green hydrogen production. Herein, a simple solvothermal process was developed to synthesize a NiMo metal–organic framework (MOF), from which a carbon-armored Ni4Mo alloy of an interwoven nanosheet structure was derived with a two-stage thermal treatment, to serve as a high-performance pH-universal HER catalyst. It requires low overpotentials of 22, 48, and 98 mV to achieve a current density of −10 mA cm–2 and 192, 267, and 360 mV to deliver an ultrahigh current density of −500 mA cm–2 in alkaline, acidic, and neutral media, respectively, and exhibits remarkable operational stability at an ultrahigh initial current density of −500 mA cm–2 for over 50 h, making it promising for applications in large-scale green hydrogen production. The success can be attributed to the unique catalyst design of a carbon-armored, composition-optimized NiMo alloy of an advantageous nanostructure of interwoven nanosheets for enhanced utilization of active sites and mass transfer of electrolytes and gaseous products, made possible with a MOF-derivation fabrication approach.

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Lithium−sulfur batteries (LSBs) are promising electrochemical energy storage devices to answer ever-increasing energy storage demands. Its practical applications, however, are impeded by several technical obstacles, with shuttling of polysulfides as the main cause. A composite approach was developed for the design of effective sulfur host materials to tackle the issue. Here, cobalt sulfide nanoparticles embedded in carved N-doped carbon nanoboxes dispersed in iron single-atom decorated multiwalled carbon nanotube porous structure, S-Co@CCNB/SAFe-MWCNT, were developed as an effective sulfur host for LSBs. The sulfur host combines the high electrical conductivity and physical polysulfide confinement capability of MWCNTs, the excellent polysulfides chemisorption capability of CoS 2 , and the high catalytic efficiency of iron single-atoms toward polysulfide conversion reactions, to achieve a high performance LSB. The S-Co@CCNB/SAFe-MWCNT based LSB delivered a high initial specific capacity of 1432 mAh g −1 at 0.1 C, with a decent specific capacity of 538 mAh g −1 maintained at 2 C. For cycling stability, a specific capacity of 550 mAh g −1 was maintained after a 500-cycle operation at 1 C, giving a low average capacity decay rate per cycle of 0.043%.