applications, including solid electrolytes, [7] energy storage/generation devices, [8][9][10] electroactive actuators, [11] strain sensors, [12,13] soft robotics, [14] stretchable touch panels, [15] membrane separation, [16] and so on.To further expand the applications of ionogels, different strategies have been reported to combine various other desirable properties with ionogels, including self-healing capability, [17][18][19] high mechanical strength and resilience, [20,21] resistance against water and organic solvents, [22,23] and self-adhesiveness. [12,24] The integration of different properties with the highly conductive and stable nature of ionogels is essential to meet the requirements for practical applications in complex scenarios. For example, very recently, Wu et al. reported a class of ionogels with underwater self-healing ability and underwater adhesiveness, which demonstrated intriguing applications such as underwater communication. However, these ionogels showed only moderate conductivity, strain-softening behavior, and moderate mechanical recoverability. [25] Although multifunctional hydrogels have been extensively studies in recent years, [26][27][28] to date, it is still a great challenge to design ionogels that combine high comprehensive performance and multiple functions.Herein, we report the design and characterization of a class of physically crosslinked multifunctional ionogels that are highly transparent (>92% in visible region), highly stretchable (up to 2066%), mechanically strong (breaking strength up to 0.72 MPa), highly conductive (up to 2.92 mS cm −1 at 25 °C), and is capable to self-heal at room temperature both in air and under water. Besides, this kind of ionogel shows excellent resistance against aqueous solutions and some organic solvents, strong underwater adhesion to diverse substrates, and can be feasibly recycled by dissolving in ethanol and reprocessed into arbitrary shapes. Moreover, the ionogel-based sensor shows sensitive and repeatable sensing signals for a wide range deformation in tension or compression, including stable strain sensing in diverse liquid media, which was used for the reliable and sensitive wearable strain sensor to monitor human's motions. Our study would provide a kind of multifunctional ionogels with excellent comprehensive performance for wearable devices and sensing applications.Ionogels have gained increasing attentions as a flexible conductive material. However, it remains a big challenge to integrate multiple functions into one gel that can be widely applied in various complex scenes. Herein, a kind of multifunctional ionogels with a combination of desirable properties, including transparency, high stretchability, solvent and temperature resistance, recyclability, high conductivity, underwater self-healing ability, and underwater adhesiveness is reported. The ionogels are prepared via one-step photoinitiated polymerization of 2,2,2-trifluoroethyl acrylate and acrylamide in a hydrophobic ionic liquid. The abundant noncovalent interactions includi...

Hybrid systems of hydrogels and metals with tough bonding may find widespread applications. Here, a simple and universal method to obtain strong adhesion between hydrogels and diverse metal surfaces, such as titanium, steel, nickel, tantalum, argentum, and aluminum, with adhesion energy up to >1000 J m−2 is reported. To achieve such, the metal surfaces are instantly modified with a linker molecule via soaking, dip‐coating, or drop‐casting. The designed linker molecule has a carboxylic acid group to bind with a metal surface, and a methacrylic group to crosslink with a hydrogel, thus bridging the interface between them. In addition, by introducing a stimulus‐responsive disulfide bond into the linker molecule, the on‐demand debonding between toughly bonded hydrogel and metal surface, which is enabled by reductive cleavage of the disulfide chemical linkage, is also demonstrated. More interestingly, after the reductive debonding, the resulting metal surface with free thiol groups can be easily rebonded with a second hydrogel without any further surface modification. The strategy may provide unique opportunities in designing hybrid devices that are suitable for complex and dynamic environments.

No abstract

No abstract

No abstract