Modulating nitrogen‐rich nitrides with favorable electron structure to enhance hydrogen production activity is challenging due to thermodynamically unfavorable characteristics. Herein, an ultrathin heterojunction of metallic Co and nitrogen‐rich nitride (Co‐Mo5N6) is prepared through the ammonia annealing process as a robust electrocatalyst for hydrogen evolution reaction (HER). Density functional theory simulations and experiments reveal that the obtained Co‐Mo5N6 enables electron redistribution between the nitrogen‐rich phase and Co for more negative H2O adsorption energy, decreasing the subsequent energetic barrier of dissociation (0.05 eV) and optimizing H* absorption (ΔGH* = 0.1 eV). The structure is connected by nanosheet (≈1.2 nm) building blocks with abundant interstitial spaces, open and connective channels, and strong capillary forces, which accelerate mass transfer and electrical conductivity. The Co‐Mo5N6 exhibits excellent HER activity with an extremely low overpotential of 19 mV at 10 mA cm−2 and Tafel slope of 29.0 mV dec−1. Notably, the required overpotential is only 280 mV to achieve a high current density of 1000 mA cm−2 which is better than commercial Pt/C. This work not only improves the understanding of the catalytic activity and the electron redistribution of nitrogen‐rich nitrides, but also presents a new strategy to design other nitrogen‐rich metal nitrides (such as W2N3, Ta5N6).

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electrocatalysts, NiMo-based carbides, [10,11] nitrides, [12,13] sulfides, [14] phosphides [15] as well as NiMo-alloy electrocatalysts [16][17][18][19][20][21] can possess remarkable HER capabilities. As the variety of NiMo-based catalysts being enriched, pure NiMo-based oxide or hydroxides have rarely been explored as HER catalysts, instead they usually are coupled with other active components for realizing efficient HER. [22,23] Meantime, it has been proved the effect of accelerating water dissociation of Ni(OH) 2 in alkali [24,25] and the superior catalytic performance of MoO 2 . [26] Herein, we speculate that the alkaline HER performance of NiMo-based (hydr) oxide is greatly underestimated.Inspired by above considerations, a novel 3D porous integrated electrocatalyst Ni(OH) 2 -NiMoO x /NF constituted of crystalline Ni(OH) 2 and amorphous NiMoO x was fabricated through ZnO templateassisted electrodeposition and subsequent KOH soaking operations. Interestingly to note, soaking alters the crystallinity of the amorphous precursor and triggers phase transformation, generating the crystalline/amorphous electrocatalyst. To deliver current densities of 10 and 200 mA cm −2 for alkaline HER, this catalyst requires overpotentials of 36 and 176 mV, respectively. It also displays a much decreased Tafel slope (38 mV dec −1 ) compared with the precursor (92 mV dec −1 ), illustrating an optimized reaction kinetics from Volmer-Heyrovsky step to Heyrovsky step. And the overpotential is only 13 mV increased after the multicurrent step stability test, manifesting its excellent durability. When composed into the two-electrode electrolyzer for ureaassisted electrolysis, a cell voltage of 1.42 V is barely demanded to achieve 10 mA cm −2 . Meanwhile, the catalytic activity can sustain for more than 40 h without declination, proving the feasibility of realizing high-efficient HER through urea-assisted electrolysis. Furthermore, the synergy effect between crystalline Ni(OH) 2 and amorphous NiMoO x are identified through contrastive experiments and the Fourier transform infrared spectroscopy (FTIR) results: Ni(OH) 2 serves for accelerating the dissociation of water (Volmer step) in alkali to generate H*, while amorphous areas are the active sites for H* adsorption and desorption through subsequent Heyrovsky and Tafel steps. This work not only fabricates the electrocatalyst of NiMo-based (hydr) oxides with brilliant HER and urea oxidation reaction (UOR) capabilities, but also discovers a new pathway for designing mixed-crystal materials for other catalysis systems.The Ni(OH) 2 -NiMoO x /NF electrocatalyst was prepared via electrodeposition and soaking operations exhibited in The achievement of effective alkaline hydrogen production from water electrolysis is an active field of research. Herein, an integrated electrode composed of crystalline Ni(OH) 2 and amorphous NiMoO x is fabricated onto nickel foam (denoted as Ni(OH) 2 -NiMoO x /NF). The hydrogen evolution reaction (HER) kinetics are optimized along with phase transformation process...

Electrochemical water splitting is a feasible method for producing environmental benignity energy of hydrogen, while high price and low availability on the earth of noble electrocatalysts constrain their global-scale application. Transition metal borides (TMBs) have displayed unique metalloid characteristic and outstanding performance for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the last few decades. Herein, recent developments of the TMBs for HER and OER are summarized. Initially, the impact factors and relevant evaluation of electrocatalytic performance are described, that is, overpotential, Tafel slope and exchange current density, stability, faradaic efficiency, turnover frequency, mass and specific activities. Moreover, the optimization strategies of borides are emphasized, which principally include coupling with effective substrates, elemental doping, phase modification, interfacial engineering, and morphology control. Finally, in order to reach the goal of application, the remaining challenges and perspectives are given to point out a direction for enhancing the performance of borides.

Background Amarogentin (AMA) is a secoiridoid glycoside extracted from Swertia and Gentiana roots and exhibits many biological effects such as antioxidative, anti‐inflammatory, and antitumor activities. Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by disorders in the regulation of multiple inflammatory cytokines. No effective cure has been found for AD now. Methods We constructed the HaCat and splenocyte model and tested the inhibitory effect of AMA on IL‐4, IL‐6, and IL‐13 secretions using enzyme‐linked immunosorbent assay (ELISA). The AD mouse model was constructed and treated with AMA, the severity of skin lesions was observed, epidermal tissue was collected, and epidermal thickness and mast cell infiltration were observed using hematoxylin and eosin and toluidine blue staining, respectively. The expression of kallikrein‐related peptidase 7 (KLK7) and filaggrin (FLG) was detected using immunostaining and Western blot analysis. The mRNA expression of KLK7 and FLG was detected using quantitative polymerase chain reaction (qPCR). Blood immunoglobulin E (IgE) secretion was detected. Results AMA inhibited IL‐6 secreted by tumor necrosis factor (TNF)‐α‐induced HaCaT cells and reduced IL‐4 and IL‐13 secreted by phytohemagglutinin (PHA)‐induced primary cells in the mice spleen. It was found that the treatment of AMA with 2,4‐dinitrochlorobenzene‐induced AD‐like mice could promote the recovery of dermatitis, reduce the score of dermatitis severity and the scratching frequency, treat the skin lesions, reduce the epidermal thickness, decrease the infiltration of mast cells, reduce the IgE level in serum, decrease the expression levels of AD‐related cytokines, increase protein and mRNA expression of FLG, and reduce the protein and mRNA expression of KLK7 in the skin tissues of AD‐like mice. Conclusion In conclusion, AMA inhibits inflammatory response at the cellular level, and AMA reduces the validation response of specific dermatitis mice, relieves pruritus, and repairs the damaged skin barrier.