Ionic skins (I-skins) hold significant potential for mimicking the complex sensory functions of human skin. However, they suffer from unstable sensing performance because the water content and temperature of I-skins are susceptible to the surrounding environment. Here, a self-detection sensing mechanism designed to address this critical issue, ensuring stable perception of multiple stimuli in I-skins, is introduced. It is demonstrated that gradient polyelectrolyte (GP) conductors possess two parameters—resistance and self-induced potential—that are responsive to temperature and water content. Through establishing the functional relations of resistance and potential against temperature and water content based on the Nernst−Planck and Arrhenius equations, respectively, the temperature and water content of resulting GP I-skins can be self-detected/calculated in real-time from the measured resistance and potential signals. Such self-detection capability allows GP I-skins not only to self-calibrate their sensing parameters for accurate detection of mechanical stimuli across varying environmental conditions but also to discern surrounding temperature and humidity in accordance with Flory−Rehner theory. This self-detection sensing mechanism offers a powerful tool for developing I-skins capable of stable perception of multiple stimuli in changing environments without complex and undesired encapsulation.
Xianliang Li,Yawei Shao,Zhihao Chen,Yanqiu Wang,Junyi Wang
In this study, a fluorescence and Fe 3+ ions-responsive cerium-based metal organic framework is decorated on phytic acid-glucose hydrothermal copolymer-coated montmorillonite (MMT@CP@Ce-MOF) nanocontainer, which was developed for Q235 carbon steel's corrosion protection and detection in solution, waterborne epoxy coatings (WEP), and solvent epoxy coatings (EP). In the solution phase, the corrosion detection ability of Q235 carbon steel was introduced, relying on the Fe 3+ ions-responsive characteristic of MMT@CP@Ce-MOF. In the coating phase, WEP and EP with good barrier effect, active anti-corrosion, self-detection, and good mechanical performance were fabricated by integrating MMT@CP@Ce-MOF nanocontainers. The EIS results indicated that 2D MMT@CP@Ce-MOF based composite coating showed better anti-corrosion performance (the |Z| f= 0.01Hz value of EP-MMT@CP@Ce-MOF and WEP-MMT@CP@Ce-MOF remained 1.33 × 10 9 Ω·cm 2 and 2.71 × 10 8 Ω·cm 2 , respectively, far higher than the bare coating) after 40 d immersion. At the same time, the Ce-MOF nanosensor could accurately reflect the occurrence of corrosion at the coating damage sites. Furthermore, high adhesion force (2–3 times higher than bare coating) and results of coating fracture surface showed that homogenously incorporated MMT@CP@Ce-MOF could improve the composite coating mechanical properties by chemical interaction with the epoxy polymer.
危险品化学品经营许可证（带存储）