The expansion of silicon volume significantly impacts the degradation of silicon anodes. The current binder-formed interface fails to effectively suppress this expansion due to the absence of rigid inorganic components. Therefore, we develop an aqueous binder-mediated interfacial engineering strategy to construct an organic/inorganic artificial interfacial layer in situ during the electrode preparation process. This artificial interfacial layer, consisting of an organic alginate–lithium citric acid–tannin derivative (LiACT) binder and inorganic Li2SiO3, is generated by a combination of chemical reactions and hydrogen bonding between tannic acid, citric acid, sodium alginate, silicon, and lithium hydroxide. The three-dimensional structure provides the LiACT binder with a strong binding force. The elasticity of LiACT, the high Young's modulus of Li2SiO3, and their fast ionic conductivity enable this artificial interfacial layer to exhibit robust rigidity-flexibility and excellent ionic-electronic transport properties. Therefore, the Si electrode coated with this artificial interfacial layer (Si@LiACT) exhibits high coulombic efficiency (99.2 % in the 5th cycle), excellent cycling stability (89.2 % capacity retention after 200 cycles), and superior rate performance (1044 mAh g−1 at 4C). These enhancements are attributed to the unique organic/inorganic artificial interfacial layer, which effectively inhibits silicon volume expansion, alleviates interfacial side reactions, and promotes interfacial charge transfer.
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