镁空气电池电解液缓蚀剂的研究

发布时间：2018-11-12 14:34

【摘要】：金属空气电池(MAB)是一种特殊类型的燃料电池,成本低、无毒、无污染、能量和功率输出高效,可作为新能源广泛使用。但镁空气电池的主要问题是镁合金在中性电解液中的自腐蚀和析氢现象严重,需要通过改变镁合金元素的组成或者电解液成分来改善镁合金的抗腐蚀性能,增强电池的储电性能。本文通过在电解液中添加缓蚀剂以改善镁合金阳极的腐蚀性能,研究镁空气电池的电化学性能,根据电化学阻抗谱图和动电位极化曲线分析缓蚀剂对镁合金(AZ31)的影响,并通过组装便携式电池,测缓蚀剂加入电池后对电池性能的影响。在镁空气电池中,镁负极的极化和腐蚀是衡量镁空气电池性能及使用的重要指标。本文通过动电位极化法和电化学阻抗谱法,研究了在8%NaCl电解液中,六水合硝酸铈(CeN3O9· 6H2O)、硝酸钇(Y(NO3)3 · 6H20)、硝酸锆(Zr(NO3)4·5H20)、硝酸镧(La(NO3)3.6H2O)和硝酸钕(Nd(NO3)3·6H2O)单个缓蚀剂以及混合缓蚀剂对AZ31负极抗腐蚀性能的影响。研究结果表明:在电解液中添加六水合硝酸铈、硝酸钇、硝酸锆、硝酸镧和硝酸钕等缓蚀剂,会在AZ31镁合金表面形成保护膜,提高镁合金的耐腐蚀性,延长电池的放电时间,增加其使用寿命。通过实验确定了六水合硝酸铈、硝酸钇、硝酸锆、硝酸钕和硝酸镧的最佳浓度分别是:1.0g/L、4.0g/L、2.5g/L、1.5g/L、3.5g/L,由阻抗计算的缓蚀率分别为 53.88%、48.26%、67.66%、44.39%、72.71%。综合考虑缓蚀剂的效果,六水合硝酸铈、硝酸锆和硝酸镧为理想缓蚀剂,其效果最佳,缓蚀效果最好。在单一缓蚀剂的基础上研究了复合缓蚀剂对镁空气电池耐腐蚀性能的影响,结果表明:六水合硝酸铈和硝酸镧可以增强镁合金的耐腐蚀性能,提高缓蚀速率,由阻抗计算的缓蚀率为78.97%,镁合金的耐腐蚀效果最好,延长电池的使用寿命。六水合硝酸铈与硝酸锆和硝酸镧与硝酸锆的混合对增强镁合金的耐腐蚀性的效果较差。复合缓蚀剂与单一缓蚀剂相比,缓蚀效果较好,电池的放电时间延长近 100min。
[Abstract]:Metal air battery (MAB) is a special type of fuel cell with low cost, non-toxic, pollution-free and efficient energy and power output, so it can be widely used as a new energy source. However, the main problem of magnesia-air battery is that the self-corrosion and hydrogen evolution of magnesium alloy in neutral electrolyte are serious, so it is necessary to improve the corrosion resistance of magnesium alloy by changing the composition of magnesium alloy elements or electrolyte composition. Enhanced battery storage performance. In this paper, the corrosion resistance of magnesium alloy anode was improved by adding inhibitor to the electrolyte, and the electrochemical performance of magnesium air battery was studied. The effect of inhibitor on magnesium alloy (AZ31) was analyzed according to electrochemical impedance spectroscopy and potentiodynamic polarization curve. The effect of corrosion inhibitor on battery performance was measured by assembling portable battery. The polarization and corrosion of magnesium anode are important indexes to evaluate the performance and use of magnesium air battery. In this paper, potentiodynamic polarization and electrochemical impedance spectroscopy were used to study the effects of cerium nitrate hexahydrate (CeN3O9 6H2O), yttrium nitrate (Y (NO3 (3 6H20), zirconium nitrate (Zr (NO3) 4 5H20 in 8%NaCl electrolyte. The effects of a single inhibitor and a mixed inhibitor of lanthanum nitrate (La (NO3 3.6H2O) and neodymium nitrate (Nd (NO3 3 6H2O on the corrosion resistance of AZ31 negative electrode were investigated. The results show that the corrosion inhibitor such as cerium nitrate hexahydrate, yttrium nitrate, zirconium nitrate, lanthanum nitrate and neodymium nitrate can form protective film on the surface of AZ31 magnesium alloy, improve the corrosion resistance of magnesium alloy and prolong the discharge time of battery. Increase its service life. The optimum concentrations of cerium nitrate, yttrium nitrate, zirconium nitrate, neodymium nitrate and lanthanum nitrate are as follows: 1.0 g / L = 4.0g / L = 2.5g / L = 1.5g / L = 3.5g / L, respectively. The corrosion inhibition rates calculated by impedance are 53.88 and 48.26 and 67.66, respectively. The inhibition rate is 44.39 and 72.71, respectively. Considering the effect of corrosion inhibitor, cerium nitrate hexahydrate, zirconium nitrate and lanthanum nitrate are ideal corrosion inhibitors. The effect of composite inhibitor on corrosion resistance of magnesium air battery was studied on the basis of a single corrosion inhibitor. The results showed that cerium nitrate hexahydrate and lanthanum nitrate could enhance the corrosion resistance and corrosion inhibition rate of magnesium alloy. The corrosion inhibition rate calculated by impedance is 78.97. The corrosion resistance of magnesium alloy is the best and the life of battery is prolonged. The mixing of cerium nitrate hexahydrate with zirconium nitrate and lanthanum nitrate with zirconium nitrate has poor effect on strengthening corrosion resistance of magnesium alloy. Compared with a single inhibitor, the composite inhibitor has a better corrosion inhibition effect, and the discharge time of the battery is prolonged by nearly 100 minutes.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM911.41

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