Carbon quantum dot-induced electrolyte structuring regulates Zn nucleation and Zn(100) texture evolution in aqueous zinc metal batteries.

Aqueous zinc metal batteries are attractive for safe and low-cost energy storage, yet their practical development remains constrained by water-induced interfacial degradation and nonuniform Zn deposition. Here, we report a carbon quantum dots (CQDs)-enabled structured electrolyte, in which acetone facilitates the homogeneous incorporation of CQDs into an aqueous Zn(TFSI)2 electrolyte, thereby reorganizing the local electrolyte environment and regulating the precursor state for Zn deposition. The resulting electrolyte exhibits measurable mesoscale heterogeneity, suppressed water reactivity, reduced corrosion tendency, and improved interfacial charge-transfer characteristics. Consequently, Zn deposition evolves from loose protrusive growth to dense and flat deposition, accompanied by a markedly enhanced Zn(100) texture. The Zn//Zn symmetric cell cycles stably for 1100 h at 1 mA cm-2 and 1 mAh cm-2, while the Zn//Cu cell shows substantially improved reversibility under deep-utilization conditions. More importantly, the Zn//Prussian blue analogue full cell with the pristine electrolyte undergoes obvious capacity decay within the first 50 cycles and fails after about 200 cycles, whereas the corresponding cell with the CQD-structured electrolyte maintains stable capacity retention and coulombic efficiency over 500 cycles. The effectiveness of this electrolyte design is further validated in pouch-cell configurations, highlighting the practical promise of CQD-induced electrolyte structuring for reversible aqueous zinc metal batteries.