Motivated by the promising result that the observed side reactions are less severe in the presence of 2,7-AQDS compared to 2,6-DHAQ, the influence of anolyte structure on these reactions was investigated further. A series of ex situ simulated-crossover experiments were used to test the performance of various anolytes at the current forefront of the AORFB field (Methods S3, Figures and Table ). In addition to 2,6-DHAQ and 2,7-AQDS, the high-performing anthraquinone 2,6-DPPAQ was tested (Methods S3 and Methods S7). showing their Lewis structures, initial percentage drop in ferricyanide concentration measured within 1 h of addition of the anolyte, and the total percentage drop in ferricyanide and quinone concentration after one week aging. Red and green boxes highlight anolytes where crossover-driven side reactions detected were significant (i.e., hydroxyl-functionalized anolytes) or minimal, respectively. Note that the change in DHPS concentration could not be quantified as the 1 H NMR peaks were broad and overlapping and could not be accurately assigned (Figure ). Out of all the anthraquinone anolytes tested, the greatest ferricyanide and quinone losses were observed for 2,6-DHAQ. One of the possible explanations for this is that the hydroxyl groups in 2,6-DHAQ, which are deprotonated in alkaline conditions, are able to coordinate with Fe 3+ . To further support this hypothesis, the two anolytes which do not have hydroxyl groups, 2,6-DPPAQ and 2,7-AQDS, displayed the lowest ferricyanide and anthraquinone losses (Table and Tables ). To determine if this phenomenon was exclusive to quinone-based anolytes, a third anolyte was tested; a high-performance phenazine anolyte with hydroxyl groups, 7,8-dihydroxyphenazine-2-sulfonic acid (DHPS, Table ), once again prepared in 1 M KOH supporting electrolyte. The total ferricyanide losses observed with DHPS were comparable to those observed with 2,6-DHAQ after 1 week aging, showing that the side reactions observed are not exclusive to anthraquinones (Table and Table -2). The initial losses in ferricyanide (i.e., those measured 1 h after addition of the anolyte) were higher than those observed with 2,6-DHAQ. This could be explained by the geometry of the hydroxyl groups in DHPS, which has hydroxyl groups in the ortho position relative to each other. Indeed, hydroxyl groups with this geometry are optimal for Fe 3+ coordination, and this geometry is commonly seen in linker molecules for iron-quinone metalorganic frameworks. This suggests that the initial loss of ferricyanide is related to the ability of the anolyte to coordinate to Fe 3+ . Interestingly, however, the total ferricyanide loss after 1 week was still greater in the presence of 2,6-DHAQ than DHPS (Table , Table -S2). This could suggest that although the initial losses are related to coordination strength between anolyte and Fe 3+ , there is an additional, slower mechanism that causes ferricyanide losses to occur over longer time periods.