Flash Heat Treatment Constructing Organic-Inorganic Hybrid Layer for High-Performance Silicon Anode

The commercialization of silicon (Si) anodes has long faced critical challenges of severe volume expansion and poor conductivity. While traditional surface coating strategies can mitigate these issues, rigid carbon coatings exhibit poor stress tolerance, and flexible organic polymers with polymer networks lack sufficient electron/ion conductivity. This study developed a novel flash heat treatment strategy. By subjecting polypyrrole (PPy)-coated nano-silicon (nmSi) to short-duration high-temperature treatment, we achieved partial carbonization of the PPy shell, resulting in a core-shell silicon material (nmSi@PCHS) featuring a unique organic polymer/inorganic carbon (PPy/C) hybrid layer. After optimizing treatment time, nmSi@PCHS-5 demonstrated optimal electrochemical performance: exceptional long-term cycling stability (1000 mAh/g after 500 cycles) and superior rate capability (1200 mAh/g at 5 A/g). The performance enhancement stems from the synergistic effect of the C/PPy hybrid shell: the carbon component significantly improves electrical conductivity and lithium-ion transport, while the retained PPy network provides inherent elasticity and toughness, effectively buffering silicon volume changes and maintaining structural integrity during cycling. This work demonstrates that flash heat treatment can create multifunctional hybrid interfacial layers that effectively optimize conductivity and mechanical resilience in synergy, offering unique insights for developing high-performance silicon-based anodes.