An Aqueous Alginate‐based Binder Modified with Zn²⁺ Ions and Prussian Blue Analogues for Enhanced Silicon Anodes

Abstract In this work, an aqueous three‐dimensional (3D) crosslinked alginate‐Zn‐Prussian blue analogue (Alg−Zn‐PBAs) binder with improved mechanical property has been constructed for Si anodes. The Alg−Zn‐PBAs aqueous binder is fabricated via Zn²⁺ ion‐induced co‐precipitation reaction of PBAs nanoparticles and ionic crosslinking reaction of Alg−Zn network. The anchored PBAs nanoparticles can be formed around the Zn²⁺ ions and offer enhanced stability due to their strong supramolecular interactions to the Alg−Zn matrix. Consequently, the Si anodes using Alg−Zn‐PBAs binder exhibits a capacity of 1372.9 mAh g⁻¹ for 200 cycles at 0.84 A g⁻¹ and a higher capacity when compared to electrodes fabricated by using Alg−Zn binder and Alg binder. This work demonstrates that the combination of PBAs and alginate via an one‐step process of Zn²⁺ ions induced co‐precipitation reaction is a better design of aqueous binders for lithium‐ion batteries system with a green synthetic process.