Engineering a stable solid electrolyte interphase (SEI) is critical for suppression of lithium dendrites. However, the formation of a desired SEI by formulating electrolyte composition is very difficult due to complex electrochemical reduction reactions. Here, instead of trial-anderror of electrolyte composition, we design a Li-11 wt % Sr alloy anode to form a SrF 2 -rich SEI in fluorinated electrolytes. Density functional theory (DFT) calculation and experimental characterization demonstrate that a SrF 2 -rich SEI has a large interfacial energy with Li metal and a high mechanical strength, which can effectively suppress the Li dendrite growth by simultaneously promoting the lateral growth of deposited Li metal and the SEI stability. The Li−Sr/Cu cells in 2 M LiFSI-DME show an outstanding Li plating/stripping Coulombic efficiency of 99.42% at 1 mA cm −2 with a capacity of 1 mAh cm −2 and 98.95% at 3 mA cm −2 with a capacity of 2 mAh cm −2 , respectively. The symmetric Li−Sr/Li−Sr cells also achieve a stable electrochemical performance of 180 cycles at an extremely high current density of 30 mA cm −2 with a capacity of 1 mAh cm −2 . When paired with LiFePO 4 (LFP) and LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathodes, Li−Sr/LFP cells in 2 M LiFSI-DME electrolytes and Li−Sr/NMC811 cells in 1 M LiPF 6 in FEC:FEMC:HFE electrolytes also maintain excellent capacity retention. Designing SEIs by regulating Li-metal anode composition opens up a new and rational avenue to suppress Li dendrites.

Autonomously self-healing hydrogels have received considerable attentions due to their capacity for repairing themselves spontaneously after suffering damage, which can provide a better stability and a longer life span. In this work, a robust and mechanically and electrically self-healing hydrogel with an efficient electromagnetic interference (EMI) shielding performance was successfully fabricated via the incorporation of multiwalled carbon nanotubes (MWCNTs) into the hydrophobically associated polyacrylamide (PAM) hydrogels by using cellulose nanofiber (CNF) as the dispersant. It was been found that CNF could not only assist the homogeneous dispersion of MWCNTs but also effectively enhance the mechanical property of the resultant hydrogels. As a result, the optimal tensile strength (≈0.24 MPa), electrical conductivity (≈0.85 S m), and EMI shielding effectiveness (≈28.5 dB) were achieved for the PAM/CNF/MWCNT composite hydrogels with 1 wt % MWCNTs and 0.3 wt % CNF, which showed 458, 844, and 90% increase over (≈0.043 MPa, ≈0.09 S m, and ≈15 dB, respectively) the PAM hydrogel. More encouragingly, these composite hydrogels could rapidly restore their electrical conductivity and EMI shielding effectiveness after mechanical damage at room temperature without any external stimulus. With outstanding mechanical and self-healing properties, the prepared composite hydrogels were similar to human skin, but beyond human skin owing to their additional satisfactory electrical and EMI shielding performances. They may offer promising and broad prospects in the field of simulate skin and protection of precision electronics.

Self‐assembly continuously gains attention as an excellent method to create novel nanoscale structures with a wide range of applications in photonics, optoelectronics, biomedical engineering, and heat transfer applications. However, self‐assembly is governed by a diversity of complex interparticle forces that cause fabricating defectless large scale (>1 cm) colloidal crystals, or opals, to be a daunting challenge. Despite numerous efforts to find an optimal method that offers the perfect colloidal crystal by minimizing defects, it has been difficult to provide physical interpretations that govern the development of defects such as grain boundaries. This study reports the control over grain domains and intentional defect characteristics that develop during evaporative vertical deposition. The degree of particle crystallinity and evaporation conditions is shown to govern the grain domain characteristics, such as shapes and sizes. In particular, the grains fabricated with 300 and 600 nm sphere diameters can be tuned into single‐column structures exceeding ≈1 mm by elevating heating temperature up to 93 °C. The understanding of self‐assembly physics presented in this work will enable the fabrication of novel self‐assembled structures with high periodicity and offer fundamental groundworks for developing large‐scale crack‐free structures.

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Silicon is considered an important anode material for solid-state batteries (SSBs) because of its unique properties in addressing key challenges associated with Li metal anodes such as dendrite formation and...