Metal-based electromagnetic interference (EMI) shielding composites are essential for ensuring electromagnetic compatibility but are often compromised by susceptibility to corrosion, especially in harsh environments. Existing strategies to mitigate coupling corrosion typically involve physical barriers, which inevitably hinder conductivity. In this study, we introduce a novel interface doping approach to fabricate lightweight Graphite@PDA/Ag@Ag composites that simultaneously enhance EMI shielding and corrosion resistance. The PDA/Ag layer selectively regulates electrons with different migration directions and energies to migrate, increasing charge transfer resistance at Ag/graphite interfaces and ensuring conductivity through a tunneling effect. This design achieves an ultralow corrosion rate of 4.313 × 10^-8 μm/yr (a billionth that of 316L stainless steel) alongside superior EMI shielding effectiveness of 109 dB in the X-band at 1.5 mm thickness. Remarkably, the composite maintains over 90 dB shielding efficiency after 7 d in NaCl solutions across various pH levels. Furthermore, simulated corrosion under South China Sea conditions predicts a coating loss of less than 0.026 μm over 7 years. This work presents a transformative approach to mitigating coupling corrosion in EMI shielding materials, offering a practical route to high-performance, corrosion-resistant composites without the need for a protective topcoat.

中文翻译：

---

用于选择性电子转变的掺杂 Ag PDA 界面策略，集成了 EMI 屏蔽和防腐蚀性能


金属基电磁干扰 （EMI） 屏蔽复合材料对于确保电磁兼容性至关重要，但通常会受到腐蚀敏感性的影响，尤其是在恶劣环境中。减轻耦合腐蚀的现有策略通常涉及物理屏障，这不可避免地会阻碍导电性。在本研究中，我们引入了一种新的界面掺杂方法来制造轻质 Graphite@PDA/Ag@Ag 复合材料，同时增强 EMI 屏蔽和耐腐蚀性。PDA/Ag 层选择性地调节具有不同迁移方向和迁移能量的电子，增加 Ag/石墨界面的电荷转移电阻，并通过隧穿效应确保导电性。这种设计实现了 4.313 × ^10-8 μm/yr 的超低腐蚀速率（是 316L 不锈钢的十亿分之一），并且在 1.5 mm 厚度的 X 波段具有 109 dB 的卓越 EMI 屏蔽效果。值得注意的是，该复合材料在各种 pH 值下在 NaCl 溶液中 7 天后仍保持超过 90 dB 的屏蔽效率。此外，南海条件下的模拟腐蚀预测 7 年内涂层损失小于 0.026 μm。这项工作提出了一种减轻 EMI 屏蔽材料中耦合腐蚀的变革性方法，为无需保护性面漆即可获得高性能、耐腐蚀复合材料提供了一种实用途径。