In Situ Growing Chromium Oxynitride Nanoparticles on Carbon Nanofibers to Stabilize Lithium Deposition for Lithium Metal Anodes.

To address the dendrite growth and interface instability of high-capacity Li metal anode, heterogeneous seed-decorated 3D host materials are expected to suppress the growth of Li dendrites. The physical stability and chemical reactivity of these nanoseeds are the decisive conditions for long cycling lithium metal batteries. Herein, carbon nanofibers decorated with uniform CrON nanoparticles (ACrCFs) are synthesized by a novel in situ growing method, where the size, composition, distribution, and migration behavior of these nanoparticles are controlled by the introduction of asphaltene. As the 3D host materials for Li anodes, ACrCFs exhibit an excellent lithiophilicity, a superior mixed ion-electron conductivity, and abundant electrochemical active sites. Thus, the ACrCF-modified Li anodes deliver a smooth Li morphology, low nucleation overpotential (10.4 mV), superior cyclic stability with 320 stable cycles (Coulombic efficiency, >98.0%) at 1 mA cm, and excellent plating/stripping stability over 1000 h. Notably, no obvious detachment or chalking of these nanoparticles occur during the cycling process. The full cell with LiFePO cathode also delivers a better rate capability with more stable cycling performance. The homogeneous CrON nanoparticles achieved by this in situ growing method also promise a facile method for the potential applications of transition-metal oxynitride for high energy density battery systems.