Beyond Isolated Active Sites: Adjacent Single-Atom-Nanoparticle Electronic Coupling Enables Lateral Lithium Growth

Precise host regulation remains pivotal for dendrite-free lithium metal anodes (LMAs). While maximizing isolated single-atom sites improves initial Li nucleation, their uniform adsorption energetics inherently confine Li to these initial sites, favoring localized vertical accumulation over lateral growth. Here we propose an adjacent single-atom-nanoparticle electronic coupling strategy to break this thermodynamic bottleneck. Via coordination-mediated laser direct writing, we construct a hierarchical porous graphene host comprising ultrafine Co nanoparticles and adjacent Co single atoms. Precursor preorganization and the ultrafast, non-equilibrium kinetics of laser processing concurrently drive in situ graphitization and Co-species reconstruction, effectively suppressing the aggregation in conventional thermal synthesis. Mechanistically, rather than relying on isolated thermodynamic traps, interfacial electronic coupling reconstructs the local d-band center and establishes a directed spatial Li adsorption-energy gradient. This thermodynamic driving force compels Li to sequentially occupy neighboring sites, effectively precluding localized vertical accumulation. Owing to this spatially regulated deposition, the high-loading Li||LiFePO₄ full cells retain 71.4% capacity after 1000 cycles at 2 C. This adjacent electronic coupling strategy transcends the isolated active sites paradigm, opening a new dimension for interfacial electronic-structure regulation in practical LMAs.