Single Zinc Atoms Immobilized on MXene (Ti₃C₂Cl_x) Layers toward Dendrite-Free Lithium Metal Anodes

Lithium (Li) metal has been considered as one of the most prospective anodes for Li-based batteries owing to its high theoretical gravimetric capacity (3860 mAh g^-1) and low potential (-3.04 V vs standard hydrogen electrode (SHE)). Unfortunately, there commonly exist uncontrollable dendrites in lithium anodes during the repeated plating-stripping processes, causing short cycle life and even short circuiting of lithium batteries. Here, single zinc atoms immobilized on MXene (Ti₃C₂Cl_x) layers (Zn-MXene) were produced to efficiently induce Li nucleation and growth. At the initial plating stage, lithium tended to nucleate homogeneously on the surface of Zn-MXene layers due to the large presence of Zn atoms and then grow vertically along the nucleated sites owing to a strong lightning rod effect at the edges, affording bowl-like lithium without lithium dendrites. Thus, a low overpotential of 11.3 ± 0.1 mV, long cyclic life (1200 h), and deep stripping-plating levels up to 40 mAh cm^-2 are obtained by using Zn-MXene films as lithium anodes.