Polyacrylonitrile (PAN)-derived Carbon Modification of Polysilazane Composite SiCNO/C as a High-performance Anode Material for Lithium-ion Batteries

Abstract

Silicon-based anodes are promising candidates for next-generation lithium-ion owing to their high theoretical specific capacity. However, their practical application is limited by their severe volume expansion and poor electronic conductivity during cycling, which results in rapid capacity fading. To address these challenges, a novel polymer-derived ceramic (PDC) precursor, PSZ/PAN, was designed and synthesized by integrating polysilazane (PSZ) with polyacrylonitrile (PAN). The synthesis involved an initial free-radical polymerization of PSZ to form a crosslinked network, followed by in situ introduction and polymerization of acrylonitrile, yielding a PSZ/PAN hybrid with an interpenetrating network structure at the molecular level. Upon pyrolysis, the resulting SiCNO/C hybrid anode exhibited a high reversible specific capacity of 1050.1 mAh·g⁻¹ at 500 mA·g⁻¹ and excellent cycling stability, retaining 73.2% of its initial capacity after 600 cycles. This molecular-level interpenetrating design of polymer-derived ceramics provides a promising strategy for the development of high-performance anode materials for lithium-ion batteries.