Synthesis of Cubic ZIF-8 Nanoparticles

Cubic ZIF-8 nanoparticles were synthesized as reported previously^{37 (link)}. Zn(OAC)₂·2H₂O (145.0 mg) was dissolved in 5.0 mL of deionized (DI) water. In a separate beaker, 2-methylimidazole (2267.3 mg) and CTAB (7.0 mg) were dissolved in 35.0 mL of DI water. The two solutions were mixed together in a 50 mL round bottom flask, and the mixture was stirred for another 5 min at 500 rpm. Then, the resulting solution was placed at room temperature for 3.0 hours. The obtained cubic ZIF-8 nanoparticles were washed with DI water for three times and collected by centrifuging at 8000 rpm (centrifugal force, 17726 g) for 10 min.