Petaloid bimetallic metal-organic frameworks derived ZnCo₂O₄/ZnO nanosheets enabled intermittent lithiophilic model...

The application of lithium metal anode (LMA) is hindered by its poor cycle life which could be caused by lithium dendrite and critical volume change during cycling. Our group previously proposed an intermittent lithiophilic model for three-dimensional (3D) composite LMA, however, the lithium electrodeposition behavior was not discussed. To verify this model, this work proposed a facile design of a petaloid bimetallic metal-organic frameworks (MOFs) derived ZnCo₂O₄/ZnO (ZZCO) nanosheets modified carbon cloth (CC), i.e. CC@ZZCO, as a 3D host to achieve the intermittent deposition of lithium (Li). The material characterizations, density functional theory (DFT) calculations, lithium electrodeposition behaviors, and the electrochemical tests were investigated and the intermittent lithium deposition behavior was firstly confirmed. Thanks to the intermittent lithiophilic model, the composite LMA enabled a prolonged lifespan of 1500 h in a symmetrical cell under challenging conditions of 5 mA h cm^-2 and 5 mA cm^-2, and can maintain stable at 10C with an ultrahigh specific capacity of 110 mAh/g. Furthermore, it can also be coupled with a LiNi_0.5Co_0.2Mn_0.3O₂ (NCM523) and a high surface load of LiFePO₄ (LFP) cathode (11.5 mg cm^-2). This research might open a window for the understanding of the Li deposition behavior and pave the way to develop other alkali-metal-ion batteries.