Dopamine (DA), one type of mussel-inspired biological molecules with adhesive nature and corrosion inhibitor property, are often used to functionalize the surfaces of various materials. Herein, we report the application of polydopamine (PDA) microcapsules as novel nanocontainers for the purpose, loading corrosion inhibitor (benzotriazole) in its shell structure, and then were embedded into epoxy coatings to provide self-healing and anti-corrosion protection for carbon steel. Fast release of benzotriazole in acidic environment caused by local corrosion and the chelating effect of PDA-Fe³⁺ can synergistically promote the formation of protective film on bare steel surface, which endows coatings with self-healing functionality. Electrochemical impedance spectroscopy (EIS), local electrochemical impedance spectroscopy (LEIS), and spray tests were conducted to evaluate the active inhibition and corrosion resistance of the loaded coatings. The scratched coating with incorporation of nanocontainers presented better protection performance, exhibiting increased R_o (oxide layer resistance) and R_ct (charge transfer resistance) during initial immersion periods. The EIS tests in long-term immersion were also performed to confirm the anti-corrosion effect of composited coatings. These results demonstrated that benzotriazole-decorated PDA capsules dramatically enhanced the self-healing properties and anti-corrosion performance of epoxy coatings with the synergistic help of PDA and benzotriazole.

多巴胺（DA）是一种具有粘着性和缓蚀性能的贻贝类生物分子，通常用于使各种材料的表面功能化。本文中，我们报道了聚多巴胺（PDA）微胶囊作为新型纳米容器的应用，目的是在其壳结构中加载腐蚀抑制剂（苯并三唑），然后将其嵌入环氧涂料中，以提供对碳钢的自修复和防腐蚀保护。局部腐蚀和PDA-Fe ³⁺的螯合作用导致酸性环境中苯并三唑的快速释放可以协同促进在裸钢表面上形成保护膜，从而赋予涂层自修复功能。进行了电化学阻抗谱（EIS），局部电化学阻抗谱（LEIS）和喷涂测试，以评估负载涂层的活性抑制和耐蚀性。掺有纳米容器的刮擦涂层具有更好的保护性能，显示出更高的R _o（耐氧化层）和R _ct（电荷转移阻力）在初始浸没期间。还进行了长期浸没的EIS测试，以确认复合涂层的防腐效果。这些结果表明，装饰有苯并三唑的PDA胶囊在PDA和苯并三唑的协同作用下，极大地增强了环氧涂料的自修复性能和防腐性能。