Uniformly inserted Fe3C nanoparticles in sericin-derived hierarchical porous carbon for high-performance Li-ion battery

Abstract

Biomass-derived carbon is considered a promising alternative to commercial graphite anode because of its renewability and tunable physical/chemical properties. However, the specific capacity and rate capability of biochar anode materials must be further enhanced to satisfy the increasing energy demand. Here, we report a facile strategy to synthesize uniform Fe3C inserted sericin-derived porous carbon (Fe3C/SC) via coordination with Fe3+ ions to the carboxylate radicals of sericin protein. The obtained composite retains a hierarchical pore structure with an interconnected carbon scaffold. In particular, the embedded Fe3C nanoparticles (NPs) in the carbon matrix will serve as a catalyst for the modification of the solid electrolyte interphase (SEI) layer during the cycles, which effectively enhance reversible capacity. The resulting anode provides high reversible capacity (584.0 mAh g−1 at 0.1 A g−1 after 150 cycles), superior rate capability (259.0 mAh g−1 at 2 A g−1) and remarkable cycling stability under high current density (219.7 mAh g−1 retention at 2 A g−1 after 600 cycles). This composite is expected to be one of the most potential anode materials for lithium-ion batteries, owning to its cost-effective, facile synthesis and efficient performance with excellent electrochemical properties.