%0 journal article
%@ 0935-9648
%A Hauck, M.,Saure, L.M.,Zeller-Plumhoff, B.,Kaps, S.,Hammel, J.,Mohr, C.,Rieck, L.,Nia, A.S.,Feng, X.,Pugno, N.M.,Adelung, R.,Schütt, F.

%D 2023
%J Advanced Materials
%N 41
%P 2302816 
%R doi:10.1002/adma.202302816
%T Overcoming water diffusion limitations in hydrogels via microtubular graphene networks for soft actuators
%U https://doi.org/10.1002/adma.202302816
41 
%X Hydrogel-based soft actuators can operate in sensitive environments, bridging the gap of rigid machines interacting with soft matter. However, while stimuli-responsive hydrogels can undergo extreme reversible volume changes of up to ≈90%, water transport in hydrogel actuators is in general limited by their poroelastic behavior. For poly(N-isopropylacrylamide) (PNIPAM) the actuation performance is even further compromised by the formation of a dense skin layer. Here it is shown, that incorporating a bioinspired microtube graphene network into a PNIPAM matrix with a total porosity of only 5.4% dramatically enhances actuation dynamics by up to ≈400% and actuation stress by ≈4000% without sacrificing the mechanical stability, overcoming the water transport limitations. The graphene network provides both untethered light-controlled and electrically powered actuation. It is anticipated that the concept provides a versatile platform for enhancing the functionality of soft matter by combining responsive and 2D materials, paving the way toward designing soft intelligent matter.