Dynamic Axial Ligand Dissociation Drives Solvent Trapping and Solvation-Shell Reconstruction for Ultra-Long-Life...

Organic electrolytes can circumvent the hydrogen evolution reaction of aqueous electrolytes, but their high desolvation energy results in slow electrochemical kinetics. Here, an axial ligand dissociation mechanism guided by a dual-descriptor framework combining Mulliken charge and maximum values of electrostatic potential (ESPmax) is proposed to unlock the latent Lewis acidity in the N,N-dimethylformamide (DMF) organic electrolyte with chlorophyll-based additives (MChl). Through systematic screening of MChl spanning diverse electronic configurations and oxidation states, Ga(OH)Chl with a hydroxy axial ligand is identified as uniquely capable of spontaneous dissociation of OH-, generating a high-activity GaChl+ species with Mulliken charge (+1.32) and ESPmax (127.28 kcal mol-1). This dynamically exposed superelectrophilic center exhibits ultrastrong Lewis acidity, which competitively immobilizes the DMF solvents, reconstructing the solvated shell from Zn2+(OTf-)1.50(DMF)2.54 to Zn2+(OTf-)2.85(DMF)0.64, and accelerating the transfer kinetics of Zn2+ in the organic electrolyte. Consequently, the Zn//Zn and Zn//Cu cells exhibit long-term stability over 11000 h at 0.5 mA cm-2 (cumulative capacity of 5.5 Ah cm-2) and high Coulombic efficiency (99.6%), respectively. Furthermore, the Zn//polyaniline cell delivers a capacity retention of 80% after 700 cycles at 1 A g-1. The work establishes axial ligand dissociation as a general design concept for breaking solvation-limited kinetics in multivalent batteries.