LAUSR

Stretchable and conductive hydrogels have emerged as promising candidates for intelligent and flexible electronic devices. Herein, based on a multibond network (MBN) design rationale, super tough and highly stretchable nanocomposite physical hydrogels are prepared, where 2D Ti3C2Tx MXene nanosheets serve as multifunctional cross-linkers and effective stress transfer centers. Further MXene-poly(acrylic acid) (PAA)-Fe3+ MBN physical hydrogels fabricated through controlled permeation of Fe3+ exhibit prominent and well-balanced mechanical properties (e.g., the tensile strength can reach 10.4 MPa and elongation at break can be as high as 3080%), attributed to the dual cross-linking network with dense Fe3+-mediated coordination cross-links between MXene nanosheets and PAA chains and sparse carboxy-Fe3+ cross-links between PAA chains. Moreover, both conductive MXene nanosheets and numerous ions endow the hydrogels with superior conductivity (up to 3.8 S m-1), strain sensitivity (high gauge factor of 10.09), and self-healing performance, showing great prospect as intelligent flexible electronics.