Boosting Zinc-Ion Storage: A Look at Interlayer Spacing and Zinc-Philic Engineering

Aqueous zinc-ion batteries (AZIBs) are gaining traction due to their high safety, low cost, and eco-friendliness. However, the cathode materials need more development. MXenes, with excellent hydrophilicity and conductivity, could be a great fit, but they have issues like slow Zn²⁺ kinetics and structural instability. A study explored different ion pre-embedded V₂CTₓ MXenes to fine-tune interlayer spacing. They found that ammonium (NH₄⁺) ions worked best. To speed up kinetics, they introduced a new technique called zinc-philic engineering.By adding ZnO nanoparticles to NH₄⁺-intercalated V₂CTₓ (NH₄-V₂CTₓ), the migration energy barrier for Zn²⁺ was significantly reduced. Tests showed a strong bond between ZnO and V₂CTₓ, improving reaction kinetics and stability. This resulted in a high reversible capacity of 256. 58 mAh g⁻¹ at 0. 1 A g⁻¹ and excellent rate capability of 173. 07 mAh g⁻¹ at 2 A g⁻¹. This research opens up a new way to modify cathode materials in AZIBs.