Nanofibrous Ni-Nanoparticle-SnO₂–Carbon Composites for Lithium Storage

A Ni nanoparticle (Ni-NP)-decorated nanofibrous SnO2–carbon nanocomposite (Ni-NP-SnO2–carbon) was synthesized from natural cellulose materials such as commercial laboratory cellulose filter paper. The nanocomposite was prepared via a layer-by-layer assembly process combined with carbonization and subsequent chemical reduction. The hierarchical three-dimensional porous structure of the as-prepared nanocomposite, replicated from the original cellulose, efficiently alleviated the substantial volume expansion during the lithiation/delithiation process and shortened lithium-ion transport path. Furthermore, the carbon matrix not only provided volume buffering but also ensured good electrode conductivity. The Ni-NPs acted as the barrier to prevent the SnO2 and Sn nanoparticles from aggregation during cycling and facilitated Li2O decomposition during the delithiation process, thereby enhancing the reversible capacity of the Ni-NP-SnO2–carbon anodes. Particularly, after 120 cycles at 100 mA g–1, the nanocomposite with 28.9 wt % of Ni content delivered an excellent reversible capacity of 772 mAh g–1.