The battery safety and cost remain major challenges for developing nextgeneration rechargeable batteries. All-solid-state sodium (Na)-ion batteries are a promising option for low-cost as well as safe rechargeable batteries by using abundant resources and solid electrolytes. However, the operation of solid-state batteries is limited due to the low ionic conductivity of solid electrolytes. Therefore, it is essential to develop new compounds that feature a high ionic conductivity and chemical stability at room temperature. Herein, we report a potassium-substituted sodium superionic conductor solid electrolyte, Na 3−x K x Zr 2 Si 2 PO 12 (0 ≤ x ≤ 0.2), that exhibits an ionic conductivity of 7.734 × 10 −4 S/cm −1 at room temperature, which is more than 2 times higher than that of the undoped sample. The synchrotron powder diffraction patterns with Rietveld refinements revealed that the substitution of large K-ions resulted in an increased unit cell volume, widened the Na diffusion channel, and shortened the Na−Na distance. Our work demonstrates that substituting a larger cation on the Na site effectively widens the ion diffusion channel and consequently increases the bulk ionic conductivity. Our findings will contribute to improving the ionic conductivity of the solid electrolytes and further developing safe next-generation rechargeable batteries.

Human hands are highly versatile. Even though they are primarily made of materials with high water content, they exhibit a high load capacity. However, existing hydrogel grippers do not possess...

Achieving strong adhesion between hydrogels and diverse materials is greatly significant for emerging technologies yet remains challenging. Existing methods using non‐covalent bonds have limited pH and ion stability, while those using covalent bonds typically lack on‐demand detachment capability, limiting their applications. In this study, a general strategy of covalent bond‐based and detachable adhesion by incorporating amine‐rich proteins in various hydrogels and inducing the interfacial crosslinking of the hydrogels using a protein‐crosslinking agent is demonstrated. The protein crosslink offers topological adhesion and can reach a strong adhesion energy of ≈750 J m−2. The chemistry of the adhesion is characterized and that the inclusion of proteins inside the hydrogels does not alter the hydrogels’ properties is shown. The adhesion remains intact after treating the adhered hydrogels with various pH solutions and ions, even at an elevated temperature. The detachment is triggered by treating proteinase solution at the bonding front, causing the digestion of proteins, thus breaking up the interfacial crosslink network. In addition, that this approach can be used to adhere hydrogels to diverse dry surfaces, including glass, elastomers and plastics, is shown. The stable chemistry of protein crosslinks opens the door for various applications in a wide range of chemical environments.

Curved hydrogel surfaces bearing chemical patterns are highly desirable in various applications, including artificial blood vessels, wearable electronics, and soft robotics. However, previous studies on the fabrication of chemical patterns...

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