Programming Closed Pores in Hard Carbon Anodes via Alcohol-Regulated Interfacial Assembly for High-Rate and Durable Sodium-Ion Storage

Closed pores are widely recognized as the primary structural domains responsible for the low-voltage plateau capacity of hard carbon anodes for sodium-ion batteries (SIBs). However, current strategies for constructing closed pores predominantly rely on post-carbonization reconstruction, offering limited control over pore accessibility and interfacial chemistry. Here we demonstrate that closed pores can instead be programmed during the precursor assembly process via an alcohol-regulated interfacial assembly strategy. By systematically modulating the alcohol/water solvent environment, hydrogen-bond interactions, micelle swelling behavior, and pyrrole polymerization kinetics are cooperatively regulated, enabling programmable precursor confinement and the subsequent transformation of micelle-pyrrole assemblies into closed-pore-rich hard carbons during carbonization. The optimized hard carbon exhibits abundant closed ultramicropores that not only facilitate the quasi-metallic sodium cluster filling but also promote the formation of a thin inorganic-rich solid electrolyte interphase (SEI) layer, thereby accelerating sodium-storage kinetics. As a result, it delivers an outstanding rate capability of 119 mAh g^-1 at 10 A g^-1 and robust cycling stability over 6000 cycles at 5 A g^-1, as well as excellent low-temperature performance at -20°C. This work establishes precursor organization programming as a general strategy for constructing closed pores in hard carbon materials toward fast-charging and long-life SIBs.