Fig. 5: Selective adsorption of dyes by Ni/Fe-MOFs.

Adsorption capacities of a Fe-MOFs, b Ni-MOFs, c Ni/Fe (3:1) MOFs, d Ni/Fe (1:1) MOFs, and e Ni/Fe (1:3) MOFs for eight dyes. Fe-MOFs favor anionic dyes (e.g., EY), Ni-MOFs adsorb cationic dyes (e.g., NR), and Ni/Fe (1:1) MOFs show enhanced AF uptake due to synergistic effects.