Ultrathin 5 μm Thick Silicon Nanowires Intercalated with Reduced Graphene Oxide Binderless Anode for Lithium-Ion Batteries

Abstract

Binderless carbon-based anode films can enhance the energy density of lithium-ion batteries; however, a major challenge is their long-term electrochemical performance stability. Herein we report ultrathin binderless anodes based on synthesized stacks of reduced multilayer graphene-oxide and silicon nanowires. A key innovation in this work is that instead of using grapheneoxide films based on disordered graphene flakes derived from chemical exfoliation, we produce large and well-ordered sheets of multilayer reduced graphene oxide by chemical vapor deposition, resulting in stronger graphene multilayers with thicknesses of ∼700 nm. The binderless anodes are prepared by building a stack of chemical vapor deposition multilayer graphene oxide with a radiofrequency-sputtered silicon coating followed by thermal annealing for the simultaneous reduction of graphene and silicon nanowire growth. This novel composition results in ∼5 μm ultrathin anodes with a specific capacity of 2247 mAh/g and a capacity retention of 842 mAh/g after 90 cycles.

Regulating the size and assembled structure of graphene building blocks for high-performance silicon nanocomposite anodes

“…S8b, ESI †). In comparison to other Si/graphene nanocomposite electrodes reported in recent studies (Table S3, ESI †), [36][37][38][39][40][41][42] our 3D composite electrode, Si@ULG-ULG, exhibits higher capacity retention at higher mass loading level. This observation highlights the potential of ultra large graphene as a promising scaffold for integrating with Si anodes, leading to enhanced stability during cycling performance.…”