Li and Zn metal batteries using organic and aqueous electrolytes,
respectively, are desirable next-generation energy storage systems
to replace the traditional Li-ion batteries. However, their cycle
life and safety performance are severely constrained by a series of
issues that are attributed to dendrite growth. To solve these issues,
a nanothick ZnO–oleic acid (ZnO–OA) composite protective
layer is developed by a facile ionic layer epitaxy method. The ZnO–OA
layer provides strong lithophilic and zincophilic properties, which
can effectively induce uniform ion deposition. As a result, the ZnO–OA
protected Li and Zn metal anodes can cycle stably for over 600 and
1000 h under a large current density of 10 mA cm–2. Employing the ZnO–OA protected anodes, the Li||LiFePO4 cell can maintain a capacity retention of 99.5% after 600
cycles at a 1 C rate and the Zn||MnO2 cell can operate
stably for 1000 cycles at 1 A g–1 current density.