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Surface self‐reconstruction via incorporating an amorphous structure on the surface of a catalyst can induce abundant defects and unsaturated sites for enhanced hydrogen evolution reaction (HER) activity. Herein, an electrochemical activation method is proposed to reconstruct the surface of a Cu‐Fe3O4 catalyst. Following a “dissolution–redeposition” path, the defective FeOOH is formed under potential stimulation on the surface of the Cu‐Fe3O4 precursor during the electrochemical activation process. This Cu‐FeOOH/Fe3O4 catalyst exhibits excellent stability as well as extremely low overpotential toward the alkaline HER (e.g., 129 and 285 mV at the large current densities of −100 and 500 mA cm−2, respectively), much superior to the Pt/C catalyst. The experimental and density functional theory calculation results demonstrate that the Cu‐FeOOH/Fe3O4 catalyst has abundant oxygen vacancies, featuring optimized surface chemical composition and electronic structure for improving the active sites and intrinsic activity. Introducing defective FeOOH on the surface of a Cu‐Fe3O4 catalyst by means of an electrochemical activation method decreases the energy barrier of both H2O dissociation and H2 generation. Such a surface self‐reconstruction strategy provides a new avenue toward the production of efficient non‐noble metal catalysts for the HER.

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A comprehensive review of the journal literature dealing with short-fiber reinforcement of various types of elastomers over the past decade indicates an underutilization of the potential for this type of reinforcing agent within the rubber industry. Whereas the properties of continuous cords are not necessarily duplicated by discontinuous fibers, a unique and useful behavior is imparted by this latter class of reinforcement to the rubber matrices containing them. In many cases, new capabilities are generated for elastomeric materials by the nature of the short fiber composite—it is not just a combination of cords and rubber, but effectively a different compound in which individual dispersed filaments can synergistically interact with the rubber, much like a polyblend or alloy. Moreover, the structure, and hence the properties, of this blend can be manipulated through the processing or fabrication operation, as well as by compounding. Thus, new opportunities are opened for growth and expansion of the classical rubber market.

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Cost-effective transition metal sulfides (TMSs) are potential electrocatalysts for alkaline hydrogen evolution reaction (HER). However, free energies of hydrogen intermediates adsorbed on the TMSs (e.g., iron sulfides) are too negative, hindering their hydrogenase-like catalytic activity. With an aim to improve the inherently catalytic activity of the TMSs, design of boron-doped Fe 7 S 8 /FeS 2 (B-Fe 7 S 8 /FeS 2 ) electrocatalysts on the base of the density functional theory (DFT) calculation results is first conducted in this work. Boron atoms doped into the Fe 7 S 8 /FeS 2 electrocatalysts are found to optimize the electronic structures of d-electrons of Fe atoms and p-electrons of S atoms. The interband energy separation between the d-orbitals of Fe atoms and the p-orbitals of S atoms in the B-Fe 7 S 8 /FeS 2 electrocatalysts is thus shorter than that of a Fe 7 S 8 or FeS 2 electrocatalyst. The optimal B-Fe 7 S 8 /FeS 2 electrocatalyst induces a boosted charge transfer process and features a low energy barrier of water dissociation and a high desorption efficiency of adsorbed hydrogen intermediates. In alkaline media, this HER electrocatalyst exhibits the overpotential of 113 mV to harvest a current density of 10 mA cm −2 . The proposed heteroatom-doping is a feasible approach to modulate electronic structures of TMS electrocatalysts and further achieve their accelerated HER kinetics.

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Hydrogen production from water splitting is one of the most promising approaches to achieve carbon neutrality when high‐performance electrocatalysts are ready for the sluggish hydrogen evolution reaction (HER). Although earth‐rich and cheap transition metal carbides (TMCs) are potential HER electrocatalysts, their platinum‐like electronic structures are severely hampered by their strong binding with hydrogen intermediates (H*). Here, a universal “balance effect” strategy is proposed, where nitrogen‐doped graphene (NG) is introduced to weaken the interactions of TMCs (M = Mo, W, Ti, and V) with H*. Hydrogen binding energies calculated by the density functional theory show that the TMCs coupled with NG appear to be thermo‐neutral. Stemming from different work functions of TMCs and NG, partial electrons transfer from TMC to the NG surface, resulting in optimized electronic structures of these electrocatalysts. These optimized electronic structures balance hydrogen adsorption and desorption, leading to synergistically‐enhanced HER kinetics. The overpotentials and Tafel slopes of the HER on these TMC@NG electrocatalysts are thus pronouncedly reduced in both acidic and alkaline solutions. This universal strategy provides a novel approach to design effective and stable TMCs as superior HER electrocatalysts. It can be expanded to other electrocatalysts for sustainable hydrogen production in different media.