Solvation Reconfiguration Enables Two‐Electron Iodine Chemistry Through Chloride Activation for High‐Energy Zn–Iodine Flow Batteries
Solvation Reconfiguration Enables Two‐Electron Iodine Chemistry Through Chloride Activation for High‐Energy Zn–Iodine Flow Batteries
研究概述
以DMF共溶剂重构电解液溶剂化环境，减弱Zn²⁺–Cl⁻缔合及氯离子水合，提高Cl⁻活性，从而稳定I⁺并实现锌–碘液流电池的双电子碘氧化还原。电池循环1000次、约1600小时容量衰减很小，库仑效率99.9%；按正极电解液体积计，放电能量密度72.88 Wh/L。
谱图与表征信息
FIGURE 1 Rational screening of cosolvents and solvation structure reconfiguration. (a) Solvent selection map of 14 common solvents as a function of the DN and α. (b) Molecular dynamics simulation snapshot of DMF-based co-solvent electrolyte (DMF electrolyte), DMSO electrolyte, EtOH electrolyte and WIS electrolyte, and representative coordination environments of Zn2+ from MD simulations. (c) Normalized Zn K-edge XANES spectra of DMF electrolyte, DMSO electrolyte, WIS electrolyte, solid ZnCl2, and Zn reference. (d) Wavelet transforms (WTs) for the k3-weighted EXAFS signals at Zn K-edge of DMF electrolyte, DMSO electrolyte, EtOH electrolyte and WIS electrolyte. Radial distribution function g(r) and cumulative radial distribution function n(r) in four electrolytes as functions of distance r between (e) Cl−and O atoms, and (f) I+ and Cl−. (g) Representative coordination environments of I+ in four electrolytes from MD simulations. (h) Photographs of four electrolytes after the addition of 0.1 M ICl and standing at room temperature for 1 h and (i) their corresponding Raman spectra.