Large-scale synthesis of silicon arrays of nanowire on titanium substrate as high-performance anode of Li-ion batteries

We have demonstrated large-scale synthesis of Si nanowire arrays (SiNA) on Ti substrate and their application as high-performance anode of Li-ion batteries. SiNA were controllably synthesized through hot-filament chemical vapour deposition (HFCVD) using Au films of different thickness as a catalyst. We found that the thickness of the Au film based catalysts played important role in controlling the morphology of Si nanostructures. The thick Au layer (e.g., 50 nm) resulted in the formation of the SiNA, while the thin Au layer (e.g., 5 nm) led to the disordered Si nanowires. The as-synthesized SiNA exhibited large reversible capacity (3600 mAh g−1) and high initial Coulombic efficiency (86.4%), which is much better than the disordered Si nanowires. The good contact and adhesion of SiNA with current collectors, as well as excellent strain accommodation might be responsible for the enhanced performance as anode of Li-ion batteries.

► Large-scale synthesis of Si nanowire arrays (SiNA) on Ti substrate were achieved. ► The SiNA showed large reversible capacity and high initial Coulombic efficiency. ► The array nanostructures might be responsible for the improved performance.