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Developing economical and efficient electrocatalysts with nonprecious metals for the hydrogen evolution reaction (HER), especially in water-alkaline electrolyzers, is pivotal for large-scale hydrogen production. Recently, both density functional theory (DFT) calculations and experimental studies have demonstrated that earth-abundant MoS 2 is a promising HER electrocatalyst in acidic solution. However, the HER kinetics of MoS 2 in alkaline solution still suffer from a high overpotential (90−220 mV at a current density of 10 mA cm −2 ). Herein, we report a combined experimental and first-principle approach toward achieving an economical and ultraefficient MoS 2 -based electrocatalyst for the HER by fine-tuning the electronic structure of MoS 2 nanorods with N and Mn dopants. The developed N,Mn codoped MoS 2 catalyst exhibits an outstanding HER performance with overpotentials of 66 and 70 mV at 10 mA cm −2 in alkaline and phosphate-buffered saline media, respectively, and corresponding Tafel slopes of 50 and 65 mV dec −1 . Moreover, the catalyst also exhibits long-term stability in HER tests. DFT calculations suggest that (1) the electrocatalytic performance can be attributed to the enhanced conductivity and optimized electronic structures for facilitating H* adsorption and desorption after N and Mn codoping and (2) N and Mn dopants can greatly activate the catalytic HER activity of the Sedge for MoS 2 . The discovery of a simple approach toward the synthesis of highly active and low-cost MoS 2 -based electrocatalysts in both alkaline and neutral electrolytes allows the premise of scalable production of hydrogen fuels.

The development of highly active, inexpensive, and stable bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts to replace noble metal Pt and RuO2 catalysts remains a considerable challenge for highly demanded reversible fuel cells and metal–air batteries. Here, a simple approach for the facile construction of a defective nanocarbon material is reported with B and N dopants (B,N‐carbon) as a superior bifunctional metal‐free catalyst for both ORR and OER. The catalyst is prepared by pyrolyzing the composites of ethyl cellulose and high‐boiling point 4‐(1‐naphthyl)benzeneboronic acid in NH3 atmosphere with an inexpensive Zn‐based template. The obtained porous B,N‐carbon with rich carbon defects exhibits excellent ORR and OER performances, including high activity and stability. In alkaline medium, B,N‐carbon material shows high ORR activity with an onset potential (E onset) reaching 0.98 V versus reversible hydrogen electrode (RHE), very close to that of Pt/C, a high electron transfer number and excellent stability. This catalyst also presents the admirable ORR activity in acidic medium with a high E onset of 0.81 V versus RHE and a four‐electron process. The OER activity of B,N‐carbon is superior to that of the precious metal RuO2 and Pt/C catalysts. A Zn–air battery using B,N‐carbon as the air cathode exhibits a low voltage gap between charge and discharge and long‐term stability. The excellent electrocatalytic performance of this porous nanocarbon material is attributed to the combined positive effects of the abundant carbon defects and the heteroatom codopants.

Aluminum‐sulfur (Al−S) chemistry is attractive for the development of next‐generation rechargeable battery systems. However, only a few reversible Al−S cells have been reported until now. This paper demonstrates that the use of an AlCl3/urea electrolyte in Al−S cells is a promising approach to improve the cycle life and reach a high discharge voltage plateau of ∼1.6–2.0 V. In contrast to the instability of sulfur in the conventional AlCl3/EMIC electrolyte, sulfur is chemically stable in the AlCl3/urea electrolyte, which allows better cell cycling stability. The Al−S cell delivers an initial capacity of ∼700 mAh gs−1 and maintains a capacity of up to ∼500 mAh gs−1 after 100 cycles.

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