Determination of Impurity Elements in Nickel-Zinc Ferrites Materials by Direct Current Glow Discharge Mass Spectrometry / 分析化学

ABSTRACT

A direct current glow discharge mass spectrometry ( GD-MS) for the determination of Li, Be, Na, Mg, Si, P, K, Ca, Ti, V, Cr, Mn, Co, Ga, Sr, Mo, Ag, Cd, Sn, Sb, W and Pb in nickel-zinc ferrites was developed. Copper powder as the conductive medium was evenly mixed with nickel-zinc ferrites powder for tableting, and then the impurity elements in nickel-zinc ferrites were determined by GD-MS. The influence of sample preparation and the glow discharge conditions including discharge current, discharge voltage, discharge gas flow rate and pre-sputter time on discharge stability and analysis sensitivity were investigated. The mass spectrometry interferences of analytes were investigated, as well as appropriate isotopes were selected. Most of the mass spectrometry interferences were avoided by measuring in medium resolution mode and high resolution mode. Total signal of Fe, Ni, Zn, O and Cu normalization was adopted, and the impurity elements in nickel-zinc ferrites were calculate in subtraction. The results showed that the detection limits for the investigated elements were in the range of 0. 001-0. 29 μg/g, the relative standard deviations of each element were within 3 . 5%-18 . 6%. The analysis results were consistent with those obtained by inductively coupled plasma mass spectrometry.