Bo Wang

N-PC@dCo/S cathode with Co/N active sites effectively suppresses polysulfide migration, accelerates K ₂ S nucleation/decomposition, and reduces sulfur redox polarization, thus leading to 868.2 mAh g ⁻¹ .

Porous carbons are indispensable for supercapacitors and as hosts for silicon anodes in next‐generation lithium‐ion batteries, yet their commercialization is crippled by the low carbon yield of phenolic resin precursors. What fundamentally controls the yield and how to improve it have long puzzled both academia and industry. Here, we address the root cause by systematically tuning the formaldehyde‐to‐phenol (F/P) molar ratio. We discover that the methylene bridge density in the cured resin is the key determinant of carbon yield. At the optimal F/P ratio of 2.0, the resin achieves the most complete crosslinked network, boosting the porous carbon yield from below 36% (PC‐1.0) to 47.15% (PC‐2.0), without compromising pore development. PC‐2.0 retains a high specific surface area of 2580.6 m ² ·g ⁻¹ and delivers an outstanding specific capacitance of 371.8 F·g ⁻¹ at 0.5 A·g ⁻¹ . Moreover, it exhibits a high capacitance retention of 95.76% after 10 000 cycles at a current density of 10 A·g ⁻¹ , demonstrating competitive advantages over various electrode materials reported in recent years. Quantitative analysis confirms a strong positive correlation between methylene content and yield, solving the long‐standing puzzle. This work provides a simple, scalable strategy to break the yield‐performance trade‐off, reducing raw material cost by 16.47% compared with commercial resin.

Sodium metal batteries (SMBs) have attracted increasing attention for low-cost energy storage because metallic sodium combines a high theoretical capacity, a low redox potential, and the resource advantage of naturally abundant sodium. However, conventional organic liquid electrolytes suffer from volatility, leakage, and flammability, which may trigger thermal runaway, fire, or even explosion under long-term cycling or abusive conditions. Herein, we develop a flame-retardant gel polymer electrolyte (GPE) via the in situ thermal polymerization of trimethylolpropane trimethacrylate (TMPTMA) and 1,6-hexanediol diacrylate (HDDA), using fluoroethylene carbonate (FEC)/trimethyl phosphate (TMP) as the solvent system and NaTFSI/NaDFOB as a dual-salt system. The three-dimensional cross-linked polymer network confines the liquid phase, suppresses solvent migration, and mitigates solvent-induced interfacial corrosion. TMP imparts flame-retardant capability, while NaDFOB regulates the local Na⁺ solvation structure by promoting an anion-enriched coordination environment. This solvation regulation favors anion-derived interfacial reactions, enabling the formation of an inorganic-rich SEI on the sodium anode and a thin, uniform CEI on the Na₃V₂(PO₄)₃ (NVP) cathode. Benefiting from homogeneous Na⁺ flux, suppressed dendrite growth, and stabilized dual interfaces, the Na||Cu cell delivers an average Coulombic efficiency of 98.12%. Moreover, the NVP|GPE|Na cell retains 87.8% capacity after 2000 cycles at 1C and 86.7% after 2000 cycles at 5C. This work provides a feasible strategy for designing flame-retardant GPEs that integrate enhanced safety with long-term cycling stability in sodium metal batteries.

The microstructure and texture evolution of non-oriented silicon steels with three distinct silicon contents (1.0, 1.6, and 3.5 wt.%) were systematically investigated throughout the entire production chain, with a specific emphasis on the normalizing and annealing behaviors of the 3.5 wt.% high-silicon steel. The results demonstrate that mold electromagnetic stirring (EMS) effectively refines the continuous casting slab, achieving over 60% equiaxed grains dominated by {100} and {110} textures. In hot-rolled sheets, increasing silicon content suppresses recrystallization from the surface to the center, establishing a pronounced through-thickness texture gradient characterized by subsurface Gaussian and core α/γ textures. While normalizing preserves the {110} Gaussian texture on the surface, subsequent cold rolling induces a critical texture transition: the initial Gaussian oriented grains fail to survive large deformations, and the α texture progressively transforms into the α* texture during annealing (800-1000 °C). Mechanistically, the elevated silicon content increases deformation resistance and recrystallization activation energy by hindering dislocation motion and reducing stacking fault energy, thereby creating a "slow nucleation, fast growth" kinetic regime. This unique recrystallization dynamic explains why high silicon steel exhibits larger grain sizes after normalizing despite a lower recrystallization fraction after hot rolling, ultimately leading to a reduction in detrimental {111} texture and an enhancement of favorable {110}/{100} components in the final annealed product.