A composite structural hydrogel comprising a graphene oxide (GO) sheet

a poly(N-isopropylacrylamide) (PNIPAM) microgel sphere and a PNIPAM segment was designed and synthesized. Combination of the GO sheets and thermoresponsive PNIPAM microsphere polymeric networks provides the hydrogels with an NIR responsive property. The oxidized groups of GO nanosheets enable the formation of a hydrogen bond interaction with the amide groups of PNIPAM chains. PNIPAM microspheres in hydrogel improve the response rate and responsive swelling ratio. By changing the concentration of GO

synthesis time of the microsphere

concentration of N-isopropylacrylamide (NIPAM) and the propotion of microspheres and GO

the light and thermal sensitivity of the hydrogel can be enhanced. Compared to traditional PNIPAM hydrogel

such hydrogels are capable of responsing to light

achieving non-contact controlled deformation with high response speed and high degree of response

which may expand the scope of hydrogel applications

such as NIR-controllled switch

and provide enhanced performance.