Controllable lithium deposition with toruloid PCF/Z-67 scaffold for dendrite-free lithium metal anodes

Abstract

Li metal anode has been considered as the most promising anode due to its high theoretical capacity and low redox potential. However, uncontrollable Li dendrites growth during Li deposition seriously shortens lifetime of Li metal anode. CNTs films have been regarded as the 3D frameworks for suppressing Li dendrites growth, whereas a relatively high density of CNTs film leads to Li depositing on the top of CNTs film, giving rise to lower efficiency of CNTs films. In this regard, PCF/Z-67 film is prepared by vacuum filtration of toruloid [email protected] on the separator. The film is auto-transferred to the surface of Li metal anode during cycling. The ZIF-67 nanoparticles increase the interspace of film, providing more space to accommodate deposited Li. Besides, the lithiophilic functional groups in the ZIF-67 are conducive to lower nucleation barrier of Li. At a current density of 1 mA cm−2, the Li||Li symmetrical cell consist of [email protected]/Z-67 foil can cycle stably for more than 1000 h with a hysteresis voltage of 8 mV, due to the synergistic effect of CNT and ZIF-67. The coulombic efficiency of the cell with PCF/Z-67 can stabilize at 95% under a current density of 1 mA cm−2 after 200 cycles. In addition, [email protected]/Z-67||LiFePO4 full cell delivers outstanding rate capacity and cycling stability compared with Li foil. The results demonstrate that the 3D porous framework assembled with [email protected] is an available strategy to enhance the electrochemical properties of Li metal anodes.