N-Doped C/ZnO-Modified Cu Foil Current Collector for a Stable Anode of Lithium-Metal Batteries

摘要

The security concerns and poor stability caused bylithium (Li) dendrites and volume changes are the main obstacles posedby the Li-metal batteries (LMBs). These serious issues need to beaddressed before LMBs can be commercialized. Herein, a simple way toprocess the ZIF-8 precursor was designed to oxidize Zn to ZnO; at thesame time, the surface of ZnO was coated with a layer of N-dopedcarbon material to prepare N-doped C/ZnO (NCZ) composite anode.As a lithiophilic framework, the NCZ composite anode acts as a steadyLi"host"during the deposition/stripping process of Li. N doping notonly improves the conductivity but also provides additional active sitesfor the deposition of Li. The LiZn alloy formed by ZnO and Li+promotes the uniform deposition and distribution of Li and mitigatesthe Li dendrite formation caused by an uneven Li-ion distribution. Theconductive carbon interconnection framework provides convenient electron/ion transmission channels and alleviates the volumechange. Combined with the above strengths, the Li/CF@NCZ composite symmetrical cell has a good cycle endurance of over 1600h with an ultralow voltage hysteresis (22 mV) at 5 mA cm-2with 5 mAh cm-2. This study presents a facile strategy for developing dendrite-free Li-metal anodes