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Abstract Simultaneously activating metal and lattice oxygen sites to construct a compatible multi-mechanism catalysis is expected for the oxygen evolution reaction (OER) by providing highly available active sites and mediate catalytic activity/stability, but significant challenges remain. Herein, Fe and S dually modulated NiFe oxyhydroxide (R-NiFeOOH@SO4) is conceived by complete reconstruction of NiMoO4·xH2O@Fe,S during OER, and achieves compatible adsorbate evolution mechanism and lattice oxygen oxidation mechanism with simultaneously optimized metal/oxygen sites, as substantiated by in situ spectroscopy/mass spectrometry and chemical probe. Further theoretical analyses reveal that Fe promotes the OER kinetics under adsorbate evolution mechanism, while S excites the lattice oxygen activity under lattice oxygen oxidation mechanism, featuring upshifted O 2p band centers, enlarged d-d Coulomb interaction, weakened metal-oxygen bond and optimized intermediate adsorption free energy. Benefiting from the compatible multi-mechanism, R-NiFeOOH@SO4 only requires overpotentials of 251 ± 5/291 ± 1 mV to drive current densities of 100/500 mA cm−2 in alkaline media, with robust stability for over 300 h. This work provides insights in understanding the OER mechanism to better design high-performance OER catalysts.

Highlights Density functional theory calculations indicates that interstitial B atoms can tune the atomic spacing of host metal Os and achieve a reversal hydrogen adsorption-distance relationship. The structure–activity relationship between the spacing of active Os atoms and catalytic activity is established. Prepared OsB2 with increasing dOs-Os of 2.96 Å presents the optimal hydrogen evolution reaction activity (8 mV @ 10 mA cm−2) and robust stability in alkaline media.

The rapid construction of water electrolysis catalysts by a sacrificing template in an electrochemical environment is rarely a concern. Herein, using a fluorine‐rich (F‐rich) nickel fluoride (NiF2) grown on nickel foam (NF) as a sacrificial template, a highly effective alkaline catalyst is designed. In terms of in situ reassembling, the NiF2 template can be transformed into nickel hydroxide (Ni(OH)2) in hydrogen evolution reaction (HER) and nickel oxyhydroxide (NiOOH) in oxygen evolution reaction (OER), respectively, after only 100 CV cycles, on account of the rapid ion exchange of F− and OH− in an electrochemical environment. Due to the presence of nanocatalytic units, abundant lattice defects, and porous large specific surface structures caused by the reconstruction, it only takes low overpotentials of 57 mV for HER and 228 mV for OER (@10 mA cm−2), with outstanding stability up to 15 d (@100 mA cm−2). Consequently, only a low cell voltage of 1.53 V (@10 mA cm−2) is needed for overall water splitting, superior to commercial noble metal catalysts as benchmarks. Meanwhile, it can output stable current densities of 10, 100, and 500 mA cm−2 approaching 10 d under constant cell voltages of 1.55, 2.0, and 2.5 V, respectively.

Abstract Designing synergistic heterogeneous catalytic interfaces is the key to developing highly compatible pH‐universal electrocatalysts for complex chemical environments. Our theoretical calculation results demonstrate that the Ru‐Ru2P heterointerface can not only promote the redistribution of charges, but also reduce the d‐band center, and then enhances the adsorption capacity of the key intermediate. However, in situ and facile synthesis of Ru‐Ru2P heterostructures is severely limited by thermodynamic obstacles. Herein, we propose a molten salt‐assisted catalytic synthesis scheme, and successfully build a series of homologous metallic Ru‐Ru2P heterostructure catalysts with different molar ratios of Ru to P under atmospheric pressure and low‐temperature (400°C). The resultant Ru‐Ru2P with rich heterostructures show the Pt‐like HER performance in different pH media. Particularly, it is prominent under alkaline conditions (18 mV @ 10 mA cm−2), which outperforms the Pt catalyst (37 mV @ 10 mA cm−2). Furthermore, Ru‐Ru2P heterostructures also show certain potential in the electrolysis of seawater to produce hydrogen. This work represents a significant supplement of high‐efficiency pH‐universal HER catalysts, and provides a new light on interface engineering in energy technology fields and beyond.

Abstract The rational construction of earth‐abundant and advanced electrocatalysts for oxygen evolution reaction (OER) is extremely desired and significant to seawater electrolysis. Herein, by directly etching Ni3S2 nanosheets through potassium ferricyanide, a novel self‐sacrificing template strategy is proposed to realize the in situ growth of NiFe‐based Prussian blue analogs (NiFe PBA) on Ni3S2 in an interfacial redox reaction. The well‐designed Ni3S2@NiFe PBA composite as precursor displays a unique spherical magic cube architecture composed of nanocubes, which even maintains after a phosphating treatment to obtain the derived Ni3S2/Fe‐NiPx on nickel foam. Specifically, in alkaline seawater, the Ni3S2/Fe‐NiPx as OER precatalyst marvelously realizes the ultralow overpotentials of 336 and 351 mV at large current densities of 500 and 1000 mA cm–2, respectively, with remarkable durability for over 225 h, outperforming most reported advanced OER electrocatalysts. Experimentally, a series of characterization results confirm the reconstruction behavior in the Ni3S2/Fe‐NiPx surface, leading to the in situ formation of Ni(OH)2/Ni(Fe)OOH with abundant oxygen vacancies and grain boundaries, which constructs the Ni3S2/Fe‐NiPx reconstruction system responsible for the remarkable OER catalytic activity. Theoretical calculation results further verify the enhanced OER activity for Ni3S2/Fe‐NiPx reconstruction system, and unveil that the Fe‐Ni2P/FeOOH as active origin contributes to the central OER activity.

Abstract Hitherto, there are almost no reports on the complete reconstruction in hydrogen evolution reaction (HER). Herein, the authors develop a new type of reconfigurable fluoride (such as CoF2) pre‐catalysts, with ultra‐fast and in‐depth self‐reconstruction, substantially promoting HER activity. By experiments and density functional theory (DFT) calculations, the unique surface structure of fluorides, alkaline electrolyte and bias voltage are identified as key factors for complete reconstruction during HER. The enrichment of F atoms on surface of fluorides provides the feasibility of spontaneous and continuous reconstruction. The alkaline electrolyte triggers rapid F− leaching and supplies an immediate complement of OH− to form amorphous α‐Co(OH)2 which rapidly transforms into β‐Co(OH)2. The bias voltage promotes amorphous crystallization and accelerates the reconstruction process. These endow the generation of mono‐component and crystalline β‐Co(OH)2 with a loose and defective structure, leading to an ultra‐low overpotential of 54 mV at 10 mA cm−2 and super long‐term stability exceeding that of Pt/C. Moreover, DFT calculations confirm that F− leaching optimizes hydrogen and water adsorption energies, boosting HER kinetics. Impressively, the self‐reconstruction is also applicable to other non‐noble transition metal fluorides. The work builds the fundamental comprehension of complete self‐reconstruction during HER and provides a new perspective to conceive advanced catalysts.

The vaginal microbiota plays a crucial role in female reproductive health and is considered a biomarker for predicting disease outcomes and personalized testing. However, its relationship with human papillomavirus (HPV) infection and cervical cancer is not yet clear. Therefore, this article provides a review of the association between the vaginal microbiota, HPV infection, and cervical cancer. We discuss the composition of the vaginal microbiota, its dysbiosis, and its relationship with HPV infection, as well as potential mechanisms in the development of cervical cancer. In addition, we assess the feasibility of treatment strategies such as probiotics and vaginal microbiota transplantation to modulate the vaginal microbiota for the prevention and treatment of diseases related to HPV infection and cervical cancer. In the future, extensive replication studies are still needed to gain a deeper understanding of the complex relationship between the vaginal microbiota, HPV infection, and cervical cancer, and to clarify the role of the vaginal microbiota as a potential biomarker for predicting disease outcomes, thus providing a theoretical basis for personalized testing.