高温水中添加微量Zn^(2+)对Inconel600合金氧化膜半导体性质的影响

Semiconductor Property of Oxide Films on Inconel600 Formed in High Temperature Water with Zinc Addition

核电站采用Zn2+注入技术减少一回路镍基材料的应力腐蚀和辐射污染.向高温水中添加微量Zn2+制备Inconel600合金表面氧化膜,用光电化学响应技术和容抗测量技术研究Zn2+对氧化膜半导体性质的影响.光电化学响应结果表明,氧化膜中不同氧化相的特征带隙宽度分别为Fe2O3 2.2 eV,Cr2O3 3.5 eV,FexNi1-xCr2O4 4.1 eV和ZnO 3.2eV;在开路电压下,无Zn2+参与生成的氧化膜表现阴极光电流响应,有Zn2+参与生成的氧化膜表现阳极光电流响应.Mott-Schottky结果表明,有Zn2+参与生成的氧化膜平带电位较负,相同极化电压下CS-C2(CSC空间电荷电容)值较大.高温水中添加微量Zn2+离子,能够改变Inconel600合金表面氧化膜的半导体性质.光电化学响应法是检测氧化膜中微量氧化相的一种灵敏且有效的方法.

Zinc addition technique is widely used in the first circuit of boiling water reactor（BWR） and pressurized water reactor（PWR） to lower the stress corrosion cracking and radioactive pollution of nickel-base alloys.An oxide film of Inconel600 with semiconductor properties was formed in high temperature water.And the semiconductor properties were changed by very little amount of zinc addition.Photoelectrochemical response and capacitance measurement were employed to investigate the oxide films formed on Inconel600 with/without zinc addition.The photocurrent of the oxide film was plotted as a function of photon energy,for separating into several parts,which can be derived from Fe2O3 with a band gap energy 2.2 eV,Cr2O3 3.5 eV,FexNi1-xCr2O4 4.1 eV besides ZnO 3.2 eV.For steady photoelectrochemical responses,the oxide film formed with zinc addition exhibited anodic photocurrent at open circle potential while the film without zinc exhibited cathodic photocurrent.Mott-Schottky plots indicates a negative movement of the flat band potential of the oxide film on Inconel600 with zinc addition to the film without zinc.At the same potential,the higher（space charge capacitance,CSC） indicated a more compact oxide film of Inconel600 with zinc addition in the high temperature water.It comes to a conclusion that the photoelectrochemical responses is a sensitive and effective method to investigate the oxide phase in the oxide film on alloy.