A super-stretchable and tough functionalized boron nitride/PEDOT:PSS/poly(N-isopropylacrylamide) hydrogel with self-healing, adhesion, conductive and photothermal activity

The development of multifunctional hydrogels that possess expected functionality and excellent mechanical properties simultaneously is still challenging. Herein, we have successfully fabricated a self-healing, conductive boron nitrogen nanosheet (f-BNNS)/PEDOT:PSS/PNIPAM hydrogel with a compressive strength of 700 kPa, a stretchability of 2666%, high adhesion and photothermal conversion capability using commercial PEDOT:PSS suspension and functionalized f-BNNS. The key in this material's design was that ample dynamic hydrogen bonding cross-linking points could be formed between PSS and f-BNNS as well as PSS and PNIPAM, both of which not only improved the mechanical properties of the gel, but also ensured self-healing and adhesion. More importantly, for the first time, we found that the hydrogen bonding of NIPAM and PSS could contribute to the enhanced conductivity of PEDOT:PSS owing to its capability to weaken the Coulomb interaction between the PEDOT and PSS chains.