Fig. 6

a Schematic of the PNIPAAm/SWCNTs hydrogel fabrication using Gel-Pak confinement channels and UV curing method. Reversible and programmable folding/unfolding of cube in response to temperature changes, resulting from the PNIPAAm/SWCNTs. (Reproduced with permission from Ref. [52], © 2011, American Chemical Society). b Images of the bent PVA/Na-MWCNTs hydrogel strip with 10%(w/w) containing Na-MWCNTs in 3 mM of Na₂CO₃ aqueous solution at 10 V/cm DC electric field. (Reproduced with permission from Ref. [53], © 2005, American Chemical Society)