基于硫化纳米零价铁的电化学腐蚀特性研究

Study on electrochemical corrosion characteristics of sulfidated nanoscale zerovalent iron

深刻解析纳米零价铁(Nanoscale zerovalent iron,nZVI)的腐蚀特性可为阐释其化学还原技术原理提供支撑。基于此,该文考察了硫化和络合剂对nZVI在水中腐蚀行为的影响规律,通过对电化学塔菲尔动力学曲线和电化学阻抗谱的分析,表明硫化与络合剂能够协同改善nZVI的抗腐蚀性能,且可提升其导电性能。通过进一步考察腐蚀开路电位-时间变化曲线,证实了S-nZVI在不同络合剂体系下的初始期腐蚀速率受到抑制。最后,系统揭示了硫化能够通过调控体系的初始传质过程而改善nZVI的腐蚀活性。

Profoundly clarifying the corrosion characteristics of nanoscale zerovalent iron(nZVI)can provide a theoretical support for elucidating its based technology for environmental application.Herein,the electrochemical tests including the Tafel,electrochemical impedance spectroscopy(EIS)and open-circuit potential vs.time(OCPT)curves were employed to investigate the corrosion behaviors of sulfidated nZVI(S-nZVI)under different solution chemistries.It was found that the corrosion resistance and electrical conductivity of nZVI could be synergistically improved by the sulfidation with complex reagents.In addition,the fitting results of the OCPT further verifies that the initial corrosion rates of S-nZVI can be inhibited by the reagents,which implying that the reactivity of nZVI can be improved through tuning the mass transfer of the reactive species.