Feng Wang

The corrosion degradation of ultra-thin copper foils remains a critical challenge for maintaining their long-term structural stability under aggressive electrochemical environments. In this work, small-size graphene (sGr) was incorporated into ultra-thin copper foils through a direct-current electrodeposition strategy to improve corrosion resistance. Compared with conventional graphene, the reduced graphene size facilitated a more uniform dispersion within the copper matrix and effectively regulated the surface morphology and crystallographic texture of the deposited copper foils. The resulting sGr/Cu composite foil exhibited reduced surface defects, enhanced (220) preferred orientation with a texture coefficient of 83.7%, and improved electrochemical corrosion resistance in 3.5 wt.% NaCl solution. Specifically, the sGr/Cu foil showed a more positive corrosion potential (−0.099 V), a lower corrosion current density (3.781 × 10⁻⁵ A·cm⁻²), and a higher charge transfer resistance (3789 Ω·cm²) compared with pure copper foil. The enhanced corrosion resistance was attributed to the synergistic effects of improved graphene dispersion, graphene-induced barrier effects, surface morphology optimization, and strengthened graphene/copper interfacial interactions. X-ray photoelectron spectroscopy analysis suggested the presence of Cu–O–C-related interfacial interactions, which may contribute to improved interfacial stability and corrosion protection. This work provides an effective strategy for designing corrosion-resistant ultra-thin copper foils through graphene size regulation and interface engineering.

Achieving ultradense zinc plating is a key prerequisite for fully exploiting the potential of aqueous zinc metal batteries for high‐energy, large‐scale energy storage. However, realizing such ideal deposition remains a major scientific challenge, severely constrained by interfacial instabilities, including dendrite growth, water‐induced hydrogen evolution reaction (HER), and heterogeneous ion flux. To address these issues, isomalt (denoted as ISO) was introduced as an electroplating solution additive to obtain an optimized zinc anode. During electroplating, ISO molecules selectively adsorbed on the Zn (101) crystal plane, inducing preferential growth of the (101) plane and the formation of a flat, dense zinc anode, which effectively suppressed the HER side reaction and dendrite growth. As a result, the modified zinc anode exhibited a HER overpotential of −1.19 V (vs. SHE) at 5 mA cm ⁻² . Zn//Zn symmetric cell assembled with the constructed anode achieved a stable cycling life of 1800 h at 5 mA cm ⁻² (1 mAh cm ⁻² ), and the Zn//Cu asymmetric cell maintained an average Coulombic efficiency (CE) of 98.7% over 2000 cycles. Furthermore, the Zn//I ₂ full cell demonstrated a high specific capacity retention of 92.6% after 10,000 cycles. To induce the preferred orientation of Zn crystals, this work provides valuable insights and will contribute to the development of high‐performance zinc anodes.

In the development of practical sodium‐ion batteries, electrochemical performance and cost efficiency of the electrode materials are vital considerations. Prussian blue analogs (PBAs) have emerged as promising cathode materials due to their affordability, high theoretical capacity, and cycling stability. However, low crystallinity can negatively impact their performance. This study introduces a straightforward “chelating agent‐assisted” method for producing highly crystalline PBAs. The resulting cathode boasts excellent characteristics, including a high capacity of 150 mAh g ⁻¹ , an initial Coulombic efficiency of 87.2 %, a long cycling lifespan of 1000 cycles, and superior rate performance. Furthermore, the study shows that the low structure distortion and high sodium diffusion coefficient can be attributed to the suppression of structural defects, as evidenced by in situ synchrotron powder diffraction. We believe these findings have the potential to enable the widespread use of PBAs in sodium‐ion batteries for an affordable and large‐scale energy storage system.