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Manganese (Mn) oxides are promising cathode materials for rechargeable aqueous Zn‐ion batteries. However, the Mn dissolution in weakly acidic electrolytes always hinders the development of better aqueous Zn–Mn batteries. Herein, a hydroxylated manganese oxide cathode material (H‐MnO2) is fabricated using an electrochemical method for stable aqueous Zn–Mn batteries without relying on the Mn2+ electrolyte additives. The partial hydroxylation of the oxides leads to charge redistribution of the material, changing the reaction thermodynamics and kinetics. Theoretical simulation suggests that the hydroxylation of manganese oxide promotes both Zn2+ adsorption thermodynamics and diffusion kinetics on the surface of H‐MnO2 but weakens the interaction between H+ and the electrode. Therefore, Zn2+ ions can be more reactive with the hydroxylated manganese oxide than H+ ions. Experimental results show that the Zn2+ insertion mechanism dominates the charge storage process of H‐MnO2, and the H+‐induced Mn dissolution reaction is effectively alleviated. Importantly, H‐MnO2 exhibits good cycling stability with 95% capacity retention over 5000 cycles at the current density of 3.8 A g−1 in the ZnSO4 electrolyte, outperforming the state‐of‐the‐art aqueous Zn–Mn batteries, even those with Mn2+ electrolyte additives. The findings provide new insights for designing stable manganese oxide cathodes in aqueous Zn–Mn batteries. [ABSTRACT FROM AUTHOR]

There has been a growing interest in developing catalysts to enable the reversible iodine conversion reaction for high‐performance aqueous zinc‐iodine batteries (AZIBs). While diatomic catalysts (DACs) have demonstrated superior performance in various catalytic reactions due to their ability to facilitate synergistic charge interactions, their application in AZIBs remains unexplored. Herein, we present, for the first time, a DAC comprising Mn−Zn dual atoms anchored on a nitrogen‐doped carbon matrix (MnZn−NC) for iodine loading, resulting in a high‐performance AZIB with a capacity of 224 mAh g−1 at 1 A g−1 and remarkable cycling stability over 320,000 cycles. The electron hopping along the Mn−N−Zn bridge is stimulated via a spin exchange mechanism. This process broadens the Mn 3dxy band width and enhances the metallic character of the catalyst, thus facilitating charge transfer between the catalysts and reaction intermediates. Additionally, the increased electron occupancy within the d‐orbital of Zn elevates Zn's d‐band center, thereby enhancing chemical interactions between MnZn−NC and I‐based species. Furthermore, our mechanism demonstrates potential applicability to other Metal‐Zn−NC DACs with spin‐polarized atoms. Our work elucidates a clear mechanistic understanding of diatomic catalysts and provides new insights into catalyst design for AZIBs. [ABSTRACT FROM AUTHOR]

Aqueous batteries with high safety and cost efficiency usually employ metallic cations as charge carriers. Recently, ammonium (NH4+) ion batteries using the nonmetal NH4+ as a charge carrier exhibit distinct electrochemical features from conventional aqueous batteries. Herein, the electrochemical performances of a bimetallic hydroxide material are systematically studied with different charge carriers in the electrolytes, including NH4+, as well as the conventional monovalent metallic cations K+ and Na+, respectively. Electrochemical results indicate that the charge storage process using NH4+ as the working ions exhibits a higher discharge plateau, smaller electrochemical polarization, and larger discharge capacity than that using conventional metallic charge carriers. Experimental characterizations and theoretical calculations suggest that the strong interaction between NH4+ and the electrode material, as well as the low NH4+‐ion diffusion barrier lead to these superior electrochemical features. The assembled NH4+‐ion battery exhibits a good energy density of 123 Wh kg(cathode+anode)−1 at the power density of 480 W kg(cathode+anode)−1. These fundamental findings are important for developing good safety, low‐cost, and high‐energy aqueous batteries with sustainable NH4+ charge carriers. [ABSTRACT FROM AUTHOR]

Vanadyl phosphate (VOPO4) is extensively studied as a cathode material for aqueous zinc‐ion batteries (AZIBs). However, due to sluggish ion migration and low electrical conductivity, VOPO4 typically exhibits moderate specific capacity below 200 mAh g−1. To address these issues, an iodine (I2)‐mediated etching method is proposed to enhance the electrochemical performance of VOPO4 for AZIBs. This method effectively regulates structural defects in VOPO4. Initially, I2 undergoes a disproportionation reaction with interlayer H2O in VOPO4, inducing crystal defects in the nanosheet structure. Additionally, the generated HI reduces V5+, further introducing oxygen vacancies in VOPO4. Both experimental and computational results indicate that moderate structural defects in VOPO4 can synergistically improve the electron transfer and ion diffusion kinetics of the electrode. However, excessive structural defects lead to crystalline amorphization and structural pulverization of VOPO4, impeding Zn2+ migration within the material. Therefore, the iodine‐mediated etched VOPO4 electrode (VOP‐I4) exhibits a high specific capacity of 249 mAh g−1 at a current density of 0.2 A g−1 and a large energy density of 300 Wh kg−1 at a power density of 246.2 W kg−1, outperforming most reported VOPO4‐based materials for AZIBs. This study provides a new avenue for developing high‐performance VOPO4 materials for energy storage applications. [ABSTRACT FROM AUTHOR]

Objective: Observational studies have shown positive associations between thyroid dysfunction and risk of sarcopenia. However, the causality of this association remains unknown. This study aimed to evaluate the potential causal relationship between thyroid dysfunction and sarcopenia using Mendelian randomization (MR)., Methods: This study collected pooled data from genome-wide association studies focusing on thyroid dysfunction and three sarcopenia-related features: low hand grip strength, appendicular lean mass (ALM), and walking pace, all in individuals of European ancestry. The primary analytical method used was inverse-variance weighted, with weighted median and MR-Egger serving as complementary methods to assess causal effects. Heterogeneity and pleiotropy tests were also performed, and the stability of the results was evaluated using the Leave-one-out., Results: The MR analysis indicated that hyperthyroidism could lead to a significant decrease in ALM in the extremities (OR = 1.03; 95% CI = 1.02 to 1.05; P < 0.001). The analysis also found that hypothyroidism could cause a notable reduction in grip strength (OR = 2.03; 95% CI = 1.37 to 3.01; P < 0.001) and walking pace (OR = 0.83; 95% CI = 0.77 to 0.90; P < 0.001). There was a significant association between subclinical hyperthyroidism and a reduced walking pace (OR = 1.00; 95% CI = 0.99 to 1.00; P = 0.041)., Conclusion: This study provides evidence that hyperthyroidism, hypothyroidism, and subclinical hyperthyroidism can all increase the risk of sarcopenia., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wei, Hou, Hei and Wang.)

Aqueous zinc-sulfur (Zn-S) batteries show great potential for unlocking high energy and safety aqueous batteries. Yet, the sluggish kinetic and poor redox reversibility of the sulfur conversion reaction in aqueous solution challenge the development of Zn-S batteries. Here, we fabricate a high-performance Zn-S battery using highly water-soluble ZnI 2 as an effective catalyst. In situ experimental characterizations and theoretical calculations reveal that the strong interaction between I - and the ZnS nanoparticles (discharge product) leads to the atomic rearrangement of ZnS, weakening the Zn-S bonding, and thus facilitating the electrochemical oxidation reaction of ZnS to S. The aqueous Zn-S battery exhibited a high energy density of 742 Wh kg (sulfur) -1 at the power density of 210.8 W kg (sulfur) -1 and good cycling stability over 550 cycles. Our findings provide new insights about the iodide catalytic effect for cathode conversion reaction in Zn-S batteries, which is conducive to promoting the future development of high-performance aqueous batteries., (© 2024 Wiley-VCH GmbH.)