Determination of trace impurity elements in MnZn ferrite powder by direct current glow discharge mass spectrometry

辉光放电质谱法测定锰铁氧体中的痕量杂质元素（英文）

An analytical method for the determination of 26 impurity elements （such as Li, Be, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, V, Cr, Co, Ni, Ga, Ge, Y, Nb, Mo, Ag, Cd, Sb, W and Pb） in MnZn ferrite powder by direct current glow discharge mass spectrometry （GD-MS） was established. MnZn ferrite powder was mixed with copper powder, used as a conductor, and pressed. The effects of MnZn ferrite powder preparation conditions and glow discharge parameters for the sensitivity and stability of signal analysis were investigated. By determining the choice of isotope and the application of the mass resolutions of 4000 （MR, medium resolution） and 10000 （HR, high resolution）, mass spectral interference was eliminated. The contents of impurity elements in MnZn ferrite powder was calculated by subtraction after normalizing the total signal of Mn, Zn, Fe, O and Cu. The results showed that the detection limit of 26 kinds of impurity elements was between 0.002 and 0.57 μg/g, and the relative standard deviation （RSD） was between 3.33% and 32.35%. The accuracy of this method was verified by the ICP-MS. The method was simple and practical, which is applied to the determination of impurity elements in MnZn ferrite powder.

建立了辉光放电质谱(GD-MS)法测定锰锌铁氧体中Li、Be、Na、Mg、Al、Si、P、S、K、Ca、Sc、Ti、V、Cr、Co、Ni、Ga、Ge、Y、Nb、Mo、Ag、Cd、Sb、W、Pb等26种杂质元素的分析方法。采用铜粉为导电材质,将锰锌铁氧体粉末与铜粉混合均匀后压片直接测定其中的杂质元素。优化了样品的制备过程,考察了辉光放电电流、放电电压、放电气体流量以及预溅射时间等放电参数对待测元素信号强度和稳定性的影响,选择合适的同位素、质谱中分辨率模式和高分辨率模式消除了质谱干扰,将Fe、Mn、Zn、O和Cu的信号作归一化处理,利用差减法计算锰锌铁氧体中26个杂质元素的含量。研究结果表明,各待测元素的检出限在0.002~0.57μg/g之间,相对标准偏差为3.33%~32.35%,采用ICP-MS法验证了分析结果一致性,表明方法的准确度好、精密度高。