Dual-Steric Hindrance\nModulation of Interface Electrochemistry\nfor Potassium-Ion Batteries

Electrolyte chemistry regulation is a feasible and effective\napproach\nto achieving a stable electrode–electrolyte interface. How\nto realize such regulation and establish the relationship between\nthe liquid-phase electrolyte environment and solid-phase electrode\nremains a significant challenge, especially in solid electrolyte interphase\n(SEI) for metal-ion batteries. In this work, solvent/anion steric\nhindrance is regarded as an essential factor in exploring the electrolyte\nchemistry regulation on forming ether-based K<sup>+</sup>-dominated\nSEI interface through the cross-combination strategy. Theoretical\ncalculation and experimental evidence have successfully indicated\na general principle that the combination of increasing solvent steric\nhindrance with decreasing anion steric hindrance indeed prompts the\nconstruction of an ideal anion-rich sheath solvation structure and\nguarantees the cycling stability of antimony-based alloy electrode\n(Sb@3DC, Sb nanoparticles anchored in three-dimensional carbon). These\nconfirm the critical role of electrolyte modulation based on molecular\ndesign in the formation of stable solid–liquid interfaces,\nparticularly in electrochemical energy storage systems.