| 摘要: |
为延缓钢筋腐蚀，采用水热法结合尿素水解在Q235钢上原位合成了Mg/Al-CO32-![]() ![]() -层状双金属氢氧化物（LDH）新型无机防锈膜，并研究了不同金属离子浓度的反应溶液对LDH膜钢片抗氯盐腐蚀能力的影响；采用X射线衍射（XRD）、衰减全反射傅里叶红外光谱（ATR-FTIR）及扫描电子显微镜（SEM）表征了LDH膜的物质组成和外貌结构特征，并用电化学测试评价了LDH膜的防腐性能.结果表明：在低金属离子浓度下制备的LDH膜结晶度较低，尺寸较大，膜厚度较小；高金属离子浓度时会生成富余的碳酸镁杂质，不利于LDH生长晶核活性位点的形成；而在c（Mg2+）=0.050 0 mol/L、c（Al3+）=0.025 0 mol/L以及c（尿素）=0.375 0 mol/L条件下通过水热法制备的Mg/Al-CO32-![]() ![]() -LDH膜具有较好的结晶度和致密性，对钢片腐蚀起到保护作用. |
| 关键词: 氯离子 钢筋腐蚀 水热法 金属离子浓度 层状双金属氢氧化物 |
| DOI：10.3969/j.issn.1007-9629.2022.09.005 |
| 分类号:TG174.36 |
| 基金项目:国家自然科学基金资助项目（U1801254，52078298，51925805） |
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| Effect of Metal Ion Concentration on In-Situ Growth of Mg/Al-CO -LDH Anti-corrosion Film on Q235 Steel |
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DONG Biqin, ZHANG Chengjie, QIN Shaofeng, HONG Shuxian
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Guangdong Provincial Key Laboratory of Durability of Binhai Civil Engineering， Shenzhen University， Shenzhen 518060， China
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| Abstract: |
A new type of Mg/Al-CO32-![]() ![]() -layered double hydroxide（LDH） inorganic film was designed and prepared on Q235 steel in situ by the hydrothermal method with urea hydrolysis for the sake of enhancing the corrosion resistance of steel matrix especially in concrete environment. X-ray diffractometer（XRD）， attenuated total reflection Fourier infrared spectroscopy（ATR-FTIR） and scanning electron microscope（SEM） were used to observe the chemical composition and structure characteristics of the LDH film. Electrochemical impedance spectroscopy and linear polarization resistance were measured to evaluate the anticorrosive performance of LDH film. The results show that the LDH film prepared under low metal ion concentration has lower crystallinity and larger size of LDH sheets with relatively lower thickness， while high metal ion concentration will generate magnesium carbonate that would limit the formation of nucleation sites for the further growth of LDH sheets. Therefore， LDH film prepared under the synthesis condition of c（Mg2+） = 0.050 0 mol/L， c（Al3+） = 0.025 0 mol/L and c（urea） = 0.375 0 mol/L has a complete crystalline layered structure and uniform coverage on the surface of the Q235 steel substrate， which has a positive effect on the corrosion resistance of steel substrate. |
| Key words: chloride steel corrosion hydrothermal method metal ion concentration layered double hydroxide（LDH） |
