It will be very interesting for many important reactions to endow highly active catalysts with momentum-transfer efficiency. However, the intrinsic magnetism of ferromagnetic catalysts is difficult to exploit due to the interaction between the catalyst and stirring devices. Herein, a catalytically active and super paramagnetic Co–carbon–rGO composite (CCGC) was synthesized and used as a nanoactuator to simultaneously achieve momentum-transfer and hydrolysis of NaBH4 or H3NBH3 for hydrogen production. The CCGC magnetically transferred momentum in a batch or continuous flow reactor. The external magnetic field can drive the catalyst to transfer momentum for excellent agitation. The catalyst can be fixed at an appointed position in the continuous flow for efficient separation. The separation of the catalyst from the reaction mixture also becomes facile. The CCGC showed superior retention as a pollutant adsorbent for the removal of Rhodamine B (Rh-B) from water in the absence of magnetic or mechanical stirring apparatus. The unique momentum-transfer properties, as well as excellent catalysis and adsorption, warrant its promising application in the corresponding fields.