Lithiated zinc oxide nanorod arrays on copper current collectors for robust Li metal anodes

Lithium (Li) metal anode is a promising high-capacity anode material and considered as a “Holy Grail” for advanced energy storage materials. However, the high reactivity and infinite volume expansion of Li metal create massive problems and severely hamper its practical applications. Herein, Cu foil decorated by a lithiated ZnO nanorod arrays is designed as an advanced current collector, in which the aligned LiZn/Li2O array skeleton not only regulates Li plating/stripping behavior along nanorods, but also reduces the local current density as well as supplies buffers for alleviating the volume change during cycling. As a result, the growth of Li dendrites on our fabricated current collector is suppressed. Furthermore, the advanced current collector exhibits high Coulombic efficiency (CE) of 93.3% after 200 cycles in Li||Cu cell under 5 mA cm−2 and long-term life over 800 h with low and stable overpotential of ~56.4 mV in Li||Li symmetrical cell at a 1 mA cm−2 under a fixed capacity of 1 mAh cm−2.