Figure 4

(a) Fe₂O₃ content (mol%) v. Cu¹⁺/Total Cu, Fe²⁺/Total Fe, and total reducing power \(\left( {\left[ {{\text{Cu}}^{1 + } } \right] + \left[ {{\text{Fe}}^{2 + } } \right]} \right)/\left( {\left[ {{\text{Cu}}} \right] + \left[ {{\text{Fe}}} \right]} \right)\) showing that the highest Fe₂O₃ content glass (#4) was the most reduced. Despite being the most reduced, glass #4 was the only composition that did not have high AM efficacy. Glass #s are labelled next to the three values for each composition. Horizontal dashed lines are used to distinguish the data for glasses #3, #5, and #6 as they have similar Fe₂O₃ contents. Data plotted is renormalized to exclude SiO₂. Cu¹⁺/Total Cu is only 0.01 greater than the total reducing power for glass #2 because the amount of Fe is just 13% of the total moles of redox species. (b) Leached Cu (ppm) after Day 1 on a log scale as a function of Cu¹⁺/Total Cu. The glass with the most Fe₂O₃ contained the most reduced Cu, which should have had the highest AM efficacy. However, high AM efficacy was not observed with this composition likely due to the low amount of total Cu released, as shown in (b).