Electrodeposited ZnO/Zn(OH)2 Nanosheets as a Functional Interface for Dendrite-Free Lithium Metal Anodes

초록

Modifying the current collector is a promising strategy to enable Li metal anodes with minimal Li consumption. Herein, a scalable electrodeposition method is introduced to construct 3D ZnO/Zn(OH)(2) nanosheets on Cu foil (ZOH NSs-Cu foil). Cu(OH)(2) nanowires are first formed via anodization, followed by electroconversion of Cu2+ and Zn2+ ions. DFT calculations reveal that the ZOH NSs-Cu foil exhibits high Li adsorption energy, imparting strong lithiophilicity and lowering the Li nucleation overpotential. The 3D nanosheet structure provides a large electrochemically active surface, reducing the effective current density. Furthermore, ZOH NSs-Cu foil exhibits low charge transfer resistance and promotes a Li2O/LiF-rich solid electrolyte interphase (SEI) layer, further reducing interfacial resistance. SEM analysis and simulations confirm uniform Li deposition on ZOH NSs-Cu foil. In asymmetric cells (1 mAh cm(-2) at 1 mA cm(-2)), ZOH NSs-Cu foil supports stable cycling for over 400 cycles. Furthermore, a full cell coupling a LiFePO4 (LFP) cathode with a Li@ZOH NSs-Cu foil anode retains high capacity with approximate to 100% Coulombic efficiency over 350 cycles at 1 C, even at an N/P ratio of approximate to 1.9. This binder-free, scalable approach offers precise Li deposition control and excellent electrochemical performance, advancing the practical application of Li metal anodes.

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