Coordination-Assisted Construction of Ultra-Fine Metal Nanoparticle Composites for Stable Sodium-Ion Battery Anodes

Ultra-fine nanoparticles (uf-NPs) embedded in hierarchical porous carbon (HPC) have been proven to possess intriguing properties for various energy storage applications, but effective synthetic control is still lacking. Herein, we present an efficient coordination anchor activation (CAA) strategy for the scalable synthesis and elaborate control of a series of uf-NPs embedded in HPC (Sb@HPC and FeSb₂@HPC as examples), which is achieved by taking advantage of the coordination capability of industrial ionic exchange resins. The in situ coordination-anchored uf-NPs and the tailored hierarchical porous HPC enables superior rate capability (533.1 mA h g^-1 at 3.30 A g^-1 for Sb@HPC, 276.0 mA h g^-1 at 5.37 A g^-1 for FeSb₂@HPC), enhanced cycling stability, and high reversible areal capacity (5.02 mA h cm^-2). Our study demonstrates a potentially scalable uf-NP synthesis strategy with industrial raw materials that can be applied to a large variety of energy materials.