fig11

Figure 11. (A) Synthesis of elastic aerogel magnets. (B) SEM image of a 98% porous magnetic aerogel containing cobalt ferrite nanoparticles after freeze-drying. (Right inset) Nanoparticles surrounding the nanofibrils. (Left insets) Photograph and schematic of the aerogel. (C) SEM image of a stiff magnetic nanopaper obtained after drying and compression. (Inset) Higher magnification image. (D) SEM image of one BC-based magnetic sample (C3) with 95 wt% of particles. Scale bars is 4 mm. Photographs of the magnetic aerogel being bent € and after being folded (F) in the dried state. (G) Magnetic hysteresis loops of BC/CoFe₂O₄ aerogels. The inset image shows the hysteresis loop of BC/CoFe₂O₄ aerogels at T = 200 °C. (H) Actuation process of the magnetic aerogel responding to the magnet where it bends and absorbs the water droplet and then recovers its initial state upon removal of the magnet. (A-H) Reproduced with permission^[71]. Copyright 2010, Nature.