Fig. 5: Microscopy analysis.

Granular ZVI reacted with 17 mM TcO₄⁻ in 80 mM NaCl for one month. a SEM micrograph of the iron oxide as a result of ZVI granules dissolution/reprecipitation; b–d EDS maps of Tc (b), Fe (c), and O (d). The maps were collected from the area outlined in white on the SEM image (a).