Boosting Zn2+ kinetics via the multifunctional pre-desolvation interface for dendrite-free Zn anodes

ZCO@Zn anode is fabricated by in-situ redox reaction, which shows a multifunctional interface with porous zincophilic channels. The ZCO@Zn cells harvest a cumulative capacity of ∼20000 mA h cm −2 via Zn 2+ pre-desolvation and kinetics improvement. • The ZCO@Zn anode enables Zn 2+ pre-desolvation and Zn 2+ kinetics improvement. • The ZCO@Zn anode harvests a cumulative capacity of ∼20000 mAh cm −2 at 10 mA cm −2 . • The as-proposed method meets the demand for large-scale manufacturing. • The full cell with ZCO@Zn anode maintains a stable operation for over 1200 cycles. Aqueous zinc ion batteries (AZIBs) are an advanced secondary battery technology to supplement lithium-ion batteries. It has been widely concerned and developed recently based on the element abundance and safety advantages. However, AZIBs still suffer from serious problems such as dendrites Zn, hydrogen evolution corrosion, and surface passivation, which hinder the further commercial application of AZIBs. Herein, an in-situ ZnCr 2 O 4 (ZCO) interface endows AZIBs with dendrite-free and ultra-low polarization by realizing Zn 2+ pre-desolvation, constraining H 2 O-induced corrosion, and boosting Zn 2+ transport/deposition kinetics. The ZCO@Zn anode harvests an ultrahigh cumulative capacity of ∼20000 mA h cm −2 (cycle time: over 4000 h) at a high current density of 10 mA cm −2 , indicating excellent reversibility of Zn deposition. Such superior performance is among the best cyclability in AZIBs. Moreover, the multifunctional ZCO interface improves the Coulombic efficiency (CE) to 99.7% for more than 2600 cycles. The outstanding electrochemical performance is also verified by the long-term cycle stability of ZCO@Zn//α-MnO 2 full cells. Notably, the as-proposed method is efficient and low-cost enough to enable mass production. This work provides new insights into the uniform Zn electrodeposition at the scale of interfacial Zn 2+ pre-desolvation and kinetics improvement.