射频辉光放电质谱法测定高纯氧化镥中73种痕量杂质元素

现有氧化镥检测方法无法覆盖全元素检测且无法满足超痕量元素的测定要求，据此，通过控制基体信号强度达到0.30 nA及以上，选择放电气体流量为0.8 mL/min,射频功率为38 W,预溅射时间为20 min,建立了粉末压片-射频辉光放电质谱法(RF-GD-MS)测定高纯氧化镥中73种杂质元素含量的方法。将RF-GD-MS测定高纯氧化镥样品中73种痕量杂质元素的结果与直流源辉光放电质谱法(DC-GD-MS)进行对比。结果表明，杂质元素测定值在0.01～2 mg/kg范围内时，两个方法的测定值比对结果较好，说明直流发射源与射频发射源针对同一样品进行测试时，并不影响杂质元素含量测试结果；但RF-GD-MS较DC-GD-MS灵敏度较高，检出限较低，RF-GD-MS部分杂质元素的检出限可达到0.001 mg/kg,而DC-GD-MS检出限只能达到0.05 mg/kg。实验方法的检出限为0.001～0.39 mg/kg,定量限为0.005～1.30 mg/kg。将实验方法应用于高纯氧化镥样品中73种痕量杂质元素的测定，结果表明：对含量(质量分数，下同)大于1 mg/kg的杂质元素，相对标准偏差(RS...

Determination of 73 trace impurity elements in high purity lutetium oxide by radio frequency glow discharge mass spectrometry

The existing method for the detection of lutetium oxide cannot cover the detection of whole elements, and also cannot meet the determination requirements of super trace elements. Therefore, a method for the determination of 73 impurity elements in high-purity lutetium oxide by pressed powder pellet-radio frequency glow discharge mass spectrometry(RF-GD-MS) was established. The intensity of matrix signal was controlled to 0.30 nA or higher. The flow rate of discharge gas was 0.8 mL/min, the radio frequency power was 38 W, and the pre-sputtering time was 20 min. RF-GD-MS was applied for the determination of 73 trace impurity elements in high-purity lutetium oxide samples, and the found results were compared with those obtained by direct current glow discharge mass spectrometry (DC-GD-MS). It was found that the determination results of two methods had good consistency when the content of impurity elements was in range of 0.01-2 mg/kg. In other words, the measurement results of impurity elements in same sample were not affected by the light source, i.e., direct current or radio frequency. But RF-GD-MS had higher sensitivity and lower limit of detection compared with DC-GD-MS. The limit of detection of some impurity elements could reach 0.001 mg/kg for RF-GD-MS method, while the limit of detection for DC-GD-MS could only reach 0.05 mg/kg. The limits of detection were in range of 0.001-0.39 mg/kg, and the limits of quantification were in range of 0.005-1.30 mg/kg. The proposed method was applied to the determination of 73 trace impurity elements in high-purity lutetium oxide samples. The results showed that the relative standard deviations(RSD,n=7) were within 10% for the impurity elements with content (mass fraction, similarly hereinafter) higher than 1 mg/kg. For the impurity elements with content in range of 0.1-1 mg/kg, the RSDs were within 20%. For the impurity elements with content lower than 0.1 mg/kg, the RSDs were within 30%. Some representative elements in high-purity lutetium oxide samples were determined according to the experimental method. The found results were compared with those obtained by inductively coupled plasma mass spectrometry (ICP-MS) in national standard methods (GB/T 12690 series) and GB/T 18115.15-2010. For the elements with content of 1 mg/kg, the determination results of two methods were consistent.