Synergistic and Continuous Coordination–Adsorption Modulation via Zinc Picolinate for Dendrite‐Free and High‐Rate Zinc Metal Anodes
Yiwei Yuan, Qiaoli Zhang, Yushuang Lin, Wenhai Xu, Xusheng Wang, Mengchao Li, Jinrui Liang, Chengkai Yang, Longtao Ren, Wen Liu
Abstract
Abstract The practical deployment of aqueous zinc‐ion batteries is critically hindered by severe anode degradation issues, primarily uncontrolled dendrite growth and parasitic reactions. This study introduces zinc picolinate (Zn(Pic) 2 ) as a novel multifunctional electrolyte additive that enables continuous and synergistic regulation of zinc deposition through dual mechanisms of anion coordination and interfacial adsorption. The picolinate anions (Pic – ) participate in the Zn 2+ solvation structure in the bulk electrolyte, effectively moderating the desolvation energy barrier and facilitating sustained ion delivery to the electrode interface. Simultaneously, Pic – anions adsorb onto the zinc electrode via synergistic interactions between the pyridinic nitrogen and carboxylate group, preferentially passivating high‐energy crystal planes and promoting highly oriented epitaxial growth along the (002) plane, thereby robustly suppressing dendrite formation. As a result, Zn||Zn symmetric cells achieve exceptional cycling stability exceeding 6 500 h at 1 mA cm −2 and 1 mAh cm −2 . The Zn||VO 2 full cell exhibits a capacity retention of 73.3% after 1 800 cycles at 1.0 A g −1 current density. This work demonstrates a unique molecular‐level strategy that integrates solvation structure modulation with crystallographic orientation control, offering a promising pathway toward highly reversible and dendrite‐free zinc anodes for advanced aqueous battery applications.