【作者】 王吉会； 闫华杰； 胡文彬；

【Author】 WANG Jihui;YAN Huajie;HU Wenbin;School of Materials Science and Engineering, Tianjin University;

【机构】 天津大学材料科学与工程学院；

【摘要】 利用水热法合成出钼酸盐插层锌铝铈水滑石材料（ZnAlCe-MoO₄ LDH）,并通过单因素实验和正交实验对水热合成过程中的n(Al³⁺)/n(Ce³⁺)摩尔比、反应温度、陈化温度等工艺参数进行了优化。利用扫描电镜、X射线衍射仪、红外光谱等对ZnAlCe-MoO₄ LDH的形貌和结构进行了表征,并通过电化学阻抗谱、X射线光电子能谱等技术研究了钼酸盐插层锌铝铈水滑石对Q235碳钢在3.5%NaCl溶液中的缓蚀性能和缓蚀机制。实验结果表明,合成的ZnAlCe-MoO₄ LDH呈片层状,片层厚度约为30nm;ZnAlCe-MoO₄ LDH的最佳制备工艺条件为n(Al³⁺)/n(Ce³⁺)摩尔比6:1,反应温度60℃,陈化温度100℃。ZnAlCe-MoO₄ LDH对碳钢在3.5%NaCl溶液中的缓蚀作用,一方面体现在ZnAlCe-MoO₄ LDH层板间的MoO2-4会与溶液中的Cl^-发生离子交换,降低了溶液中的Cl-含量;另一方面释放到溶液中的MoO₄^2-会与Fe²⁺、Fe³⁺形成钼酸盐钝化膜,且层板上释放出的Zn²⁺和Ce³⁺会与OH^-形成氢氧化物沉积膜,从而减缓了Q235钢在3.5%NaCl溶液中的腐蚀速率。更多还原

【Abstract】 Molybdate intercalated ZnAlCe layered double hydroxide（ZnAlCe-MoO₄ LDH） was synthesized by using solvothermal method, and the preparation parameters such as n(Al³⁺)/n(Ce³⁺) ratio, reaction temperature and transition temperature were optimized by single factor and orthogonal experiments. The surface morphology and structure of prepared ZnAlCe-MoO₄ LDH were observed and determined by scanning electron microscopy（SEM）, X-ray diffractometer（XRD） and Fourier transform infrared spectroscopy（FT-IR） methods. The inhibition behavior and mechanism of ZnAlCe-MoO₄ LDH for Q235 steel in 3.5% NaCl solution were investigated by electrochemical impedance spectroscopy（EIS） and X-ray photoelectron spectrometer（XPS）. The experimental results show that the synthesized ZnAlCe-MoO₄ LDH is in a plate-like shape with the thickness of 30 nm. The optimum preparation conditions are n(Al³⁺)/n(Ce³⁺) ratio of 6:1, reaction temperature of 60℃ and crystallization temperature of 100℃. The inhibition effects of ZnAlCe-MoO₄ LDH on the corrosion of Q235 steel in 3.5% NaCl solution are obtained by the reduction of chloride concentration in 3.5% NaCl solution owing to the anion exchange with molybdate and the formation of passive film with the composition of ferrous or iron molybdate and deposition film with zinc and cerium hydroxides.更多还原