Aqueous electrolyte‐based batteries have attracted increasing attention because of nonflammability, low cost, high power density, and environmental friendliness. However, the low energy density of aqueous lithium‐ion batteries caused by the narrow stable electrochemical window of water and electrode materials with low capacity severely limits their further development. In this regard, the development of metal anodes with high specific capacity shows excellent prospects. For example, metal zinc and aluminum anodes have high theoretical specific capacity, rich resources, and environmental friendliness, and can be used as promising anodes for high‐energy‐density aqueous rechargeable metal batteries. Unfortunately, metal anodes usually face balance issues with regard to stability and activity associated with dendrite growth and undesired side reactions in water‐based electrolytes, which is still a great challenge for aqueous metal batteries. In this review, various aqueous metal batteries including aqueous rechargeable metal batteries and aqueous metal–air batteries are summarized and highlighted. Recent advances in the design of high‐safety aqueous electrolytes and the strategies for metal anode protection are comprehensively reviewed. In addition, emerging challenges and some perspectives on the development of high‐energy‐density aqueous metal batteries are included.

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Depending on the experimental conditions and plasmonic systems, the correlations between near-field surface enhanced Raman scattering (SERS) behaviors and far-field optical responses have sometimes been accepted directly, or argued, or explored. In this work, we have numerically demonstrated the anomalous spectral correlations between the near- and far-field properties for roughened Au mesoparticles. As a counterexample, it is witnessed that the dipole extinction peak of the mesoparticles may mislead us in seeking favorable SERS performance. The simple Rayleigh scattering spectra can also be misguided in the presence of dark modes. For roughened mesoparticles with a moderate size here, the huge near-field enhancement is a synergistic result of the overall dark quadrupole mode and the substructural bonding dipole coupling. The conclusions demonstrated here would be of general interest to the field of plasmonics, especially the optimization of single-particle SERS substrates.

Different from extensively documented zirconium-cluster-based frameworks, discrete molecular assemblies based on zirconium hexanuclear clusters have scarcely been reported, mainly due to the lack of control over the connectivity of clusters. In this work, we propose a new strategy for controlling the highly connected Zr clusters and report two unprecedented discrete Zr-based metal–organic systems, a {Zr72} metal–organic cage (IAM-5) based on Zr12 clusters and a {Zr24} metal–organic macrocycle (IAM-6) based on Zr6 clusters. Structural analyses reveal that the combination of a unique bowl-shaped geometry, deliberately controlled bridging angles, and conformational flexibility brings a characteristic coordination geometry to the ligand, with significant effects and controls on the connectivities of Zr clusters as low as 4 for Zr12 nodes in IAM-5 and 2 for Zr6 nodes in IAM-6, consequently directing the formation of discrete rather than extended structures.