Adjustable interfacial adhesion is of great significance in smart‐hydrogel‐related engineering fields. This study presents an electroadhesion strategy for universal and ultrastrong hydrogel bonding with electrically programmable strength. An ionic hydrogel containing lithium ions is designed to achieve hydrated‐ion‐diffusion‐mediated interfacial adhesion, where external electric fields are employed to precisely control spatiotemporal dynamics of the ion diffusion across ionic adhesion region (IAR). The hydrogel can realize a universal, ultrastrong, efficient, tough, reversible, and environmentally tolerant electroadhesion to diverse hydrogels, whose peak adhesion strength and interfacial adhesion toughness are as high as 1.2 MPa and 3750 J m−2, respectively. With a mechanoelectric coupling model, the dominant role of the hydrated ions in IAR played in the interfacial electroadhesion is further quantitatively revealed. The proposed strategy opens a door for developing high‐performance adhesion hydrogels with electrically programmable functions, which are indispensable for various emerging fields like flexible electronics and soft robotics.

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ZrO2 films with one, two, and three layers were prepared on a 304 stainless steel surface through the sol-gel method, followed by sintering at 500, 600, and 700 °C. The crystal structure and the surface morphology of the films were characterized by X-ray diffraction and atomic force microscopy. The corrosion resistances of uncoated and coated specimens were studied by electrochemical corrosion tests in a 5% NaCl solution at room temperature. The tribological properties of ZrO2 films were investigated using a tribometer. The results showed that the crystal structure of ZrO2 partially transformed from the tetragonal phase to the monoclinic phase with a rise in sintering temperature. The grain size of the ZrO2 films grew, and the surface roughness of the films increased. However, with an increase in the number of film layers, the grain size and the surface roughness of the ZrO2 films decreased and the films became more uniform and denser. ZrO2 films effectively enhanced the corrosion and wear resistances of the stainless steel surface. With the increase of the sintering temperature and the number of layers in the film, the corrosion resistance of the ZrO2 films increased gradually, but the wear resistance of the films slowly decreased. The film with three layers, which was sintered at 700 °C, had the highest corrosion resistance. Nevertheless, the film with one layer, which was sintered at 500 °C, exhibited relatively well wear resistance.

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