The design of new materials with two or more functional groups must be strongly considered to achieve multifunctional coatings with outstanding properties such as active–passive protection against corrosion, low-friction, antifouling, and sensing, among others. In this sense, nanocomposites based on solvent-free epoxy resin/bifunctionalized reduced graphene oxide layers with NH₂ and NH₃⁺ groups (ER/BFRGO) with super-anticorrosive properties are for the first time reported here. The amine groups (−NH₂) act as cross-linker agents, which react with epoxy terminal groups from resin, thus closing the gap between the BFRGO layers and the polymeric matrix. Meanwhile, the ammonium ions (−NH₃⁺) are effective trapping agents of negatively charged atoms or molecules (e.g., Cl^–). This novel combination enables us to obtain nanocomposite coatings with passive–active protection against corrosion. ER/BFRGO deposited onto A36 mild steel exhibited a remarkably enhanced barrier against corrosion into a saline medium (1 M NaCl; 58.4 g/L), wherein the corrosion current density (i_corr) was diminished 6 orders of magnitude (i_corr = 5.12 × 10^–12 A/cm²), with respect to A36 mild steel coated only with ER (i_corr = 2.34 × 10^–6 A/cm²). Also, the highest polarization resistance R_p = 6.04 × 10⁷ Ω/cm² was obtained, which represents the lowest corrosion rate and corresponds to 3 orders of magnitude higher than A36 mild steel coated with ER (R_p = 1.43 × 10⁴ Ω/cm²). The strategy of bifunctionalization proposed herein to obtain bifunctionalized reduced GO with NH₂ and NH₃⁺ groups has not been disclosed in the literature before; in consequence, this work opens a new pathway toward the design of smart materials based on multifunctional nanomaterials.

中文翻译：

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基于双功能还原氧化石墨烯的超级防腐材料。

必须强烈考虑采用具有两个或多个官能团的新材料来设计具有优异性能的多功能涂料，例如主动-被动保护以防腐蚀，低摩擦，防污和感测等。从这个意义上讲，这里首次报道了基于无溶剂环氧树脂/具有NH ₂和NH ₃ ⁺基团的双官能化还原氧化石墨烯层（ER / BFRGO）的纳米复合材料，具有超强防腐性能。胺基（-NH ₂）充当交联剂，与树脂中的环氧端基反应，从而缩小了BFRGO层和聚合物基体之间的间隙。同时，铵离子（-NH ₃ ⁺）是带负电的原子或分子（例如Cl ^–）的有效捕集剂。这种新颖的组合使我们能够获得具有被动-主动防腐蚀保护作用的纳米复合涂层。沉积在A36低碳钢上的ER / BFRGO表现出显着增强的抗盐碱介质腐蚀能力（1 M NaCl; 58.4 g / L），其中腐蚀电流密度（i _corr）降低了6个数量级（i _corr = 5.12） ×10 – ¹² A / cm ²），相对于仅涂有ER的A36低碳钢（i _corr = 2.34×10 ^–6 A / cm ²）。还有，最高的极化电阻R_p = 6.04×10 ⁷ Ω/厘米²得到，它代表了最低腐蚀速率和对应于3个数量级比涂有ER（A36软钢更高- [R _p = 1.43×10 ⁴ Ω/厘米²）。本文提出的双官能化策略获得具有NH ₂和NH ₃ ⁺基团的双官能还原GO之前尚未公开。因此，这项工作为基于多功能纳米材料的智能材料设计开辟了一条新途径。