γ-Fe2O3@Ag-mSiO2NH2 magnetic Janus micromotor for active water remediation

Micromotors have hold great promise for environmental remediation. Herein, we reported a novel γ-Fe 2 O 3 @Ag-mSiO 2 NH 2 magnetic Janus micromotor for dynamic removal of heavy metal ions and organic pollutants from water. The as-prepared Janus micromotors displayed unique core-shell structure composed of amino-functionalized meso‑SiO 2 shell and γ-Fe 2 O 3 magnetic core, and could be propelled by O 2 bubbles generated by Ag-catalyzed decomposition of H 2 O 2 . This Janus micromotor could move with a high velocity of 203.06 ± 10.6 μm s −1 (about 253.8 body lengths s –1 ) in 10 wt.% H 2 O 2 solution. γ-Fe 2 O 3 @Ag-mSiO 2 NH 2 magnetic Janus micromotor showed much higher removal capacities for Cu 2+ (15.59 mg g −1 ) and doxycycline (31.45 mg g −1 ) than its static control samples due to the synergy of self-propulsive movement and amino-functionalized porous core-shell structure. Furthermore, the magnetic γ-Fe 2 O 3 cores enabled the remote magnetic control on the movement direction and magnetic recycling. This work provides a new strategy for environmental pollutants treatment.