Reviving Zn Dendrites to Electroactive Zn <sup>2+</sup> by Ion Sieve Interface
Zhenjie Liu, Murong Xi, Guanjie Li, Yudai Huang, Lei Mao, Jun Xu, Wei Wang, Zihan Qi, Juan Ding, Shilin Zhang, Zaiping Guo
Abstract
Abstract Zn 0 dendrite formation during repeated plating/stripping processes limits the practical use of Zn‐metal anodes in reliable and affordable energy storage. Traditional methods, including dendrite suppression and dendrite regulation, fail under demanding performance conditions due to Zn 2+ diffusion limitations and concentration gradients. Here, using an in situ pre‐zincation approach, a Li 2 Zn x Ti 3‐x O 8 (LZTO, 0<x<3) layer with uniform ion channels is introduced. This layer acts as an ionic sieve, reviving Zn 0 dendrite into Zn 2+ through redox reactions and enhancing Zn 2+ diffusion kinetics. Experiment and simulation results reveal that Zn 2+ migrates along the (111) crystal plane of LZTO through the successive replacement of Zn atoms in tetrahedral positions, with a high transference number of 0.796. LZTO@Zn performs better in coin cells at high currents (e.g., 50 mA cm −2 ) and operates at higher Zn utilization (300 h at 56.98% Zn utilization), with four times the lifespan at −40 °C and six times longer in alkaline electrolytes compared to bare Zn. Pouch cells with LZTO@Zn anodes operate in a low N/P ratio (6.9) and lean electrolyte (E/C is 20 µL mA h −1 ), achieving enhanced cycling stability. The findings indicate the significance of ion sieves with ordered ion channels in mitigating Zn 0 dendrites and promoting rapid Zn 2+ transport.