Lithiophilic CoNiB Quantum Dots Embedded in N‐Doped Porous Carbon as Multifunctional Interlayer for Dendrite‐Free and Stable Lithium Metal Batteries

ABSTRACT Lithium metal batteries (LMBs) promise ultrahigh energy density, yet their advancement is impeded by dendritic lithium growth and unstable interfacial behavior. Herein, for the first time, we present novel lithiophilic CoNiB quantum dots embedded in nitrogen‐doped hollow carbon nanorods (CoNiB@NC) as a multifunctional interlayer on a polypropylene separator for dendrite‐free and stable lithium metal batteries. The CoNiB@NC interlayer has several advantages: The uniformly distributed CoNiB quantum dots serve as highly lithiophilic nucleation centers to induce homogeneous lithium plating/stripping and form stable SEI to inhibit the growth of Li dendrites but also act as a lithiophilic layer and a strengthened physical barrier to enhance the electrolyte wettability and mechanical/thermal stability; the N‐doped porous carbon scaffold ensures fast ion/electron transport and accommodates interfacial volume changes; and the boride‐rich interface further enhances interfacial stability by modulating local electronic distribution. Benefiting from the merits mentioned above, symmetric Li//Li cells exhibit stable cycling over 500 h at 1 mA cm −2 , whereas Li//LiFePO 4 full cells maintain a high initial capacity of 144.7 mAh g −1 and a reversible capacity of 104.4 mAh g −1 at 1C over 200 cycles. This work provides new insight into the rational design, facile fabrication, and performance enhancement mechanisms of multifunctional interlayers for dendrite‐free and stable LMBs.