SnO 2 /Sn Nanoparticles Embedded in an Ordered, Porous Carbon Framework for High‐Performance Lithium‐Ion Battery Anodes

Tin dioxide (SnO 2 ) is recognized as one of the most promising anode materials for lithium‐ion batteries. However, the large volume changes of pure SnO 2 anodes during Li + insertion/extraction inevitably result in rapid capacity decay. Herein, the fabrication of microsized, porous SnO 2 /Sn/carbon (p‐SnO 2 /Sn/C) composites by a straightforward one‐step hydrothermal process with triblock copolymer Pluronic F‐127 as templating agent and subsequent carbonization is reported. In this composite structure, SnO 2 /Sn nanoparticles (≈5 nm) are uniformly embedded in an ordered porous carbon matrix to form an interpenetrating framework structure. The ordered porous carbon matrix not only offers three‐dimensional channels for extraction/insertion of Li + during cycling, but also buffers severe volume changes of the SnO 2 /Sn nanoparticles. Furthermore, the composite structure also ensures formation of stable solid electrolyte interface films as compared with isolated SnO 2 /Sn nanoparticles, which efficiently improves the electrochemical stability of the active materials. Thus, the p‐SnO 2 /Sn/C anode delivers a high reversible capacity of 1016.2 mAh g −1 at 100 mA g −1 after 100 cycles and has remarkable long‐term cycle stability (a charge capacity of 710 mAh g −1 even after 600 cycles at 1000 mA g −1 ).