Schirmer Thomas, Ulrich Thomas
Institute of Disposal Research, Clausthal University of Technology, Adolph-Römer-Str. 2A, D- 38678, Clausthal-Zellerfeld, Germany.
Sci Rep. 2025 Mar 6;15(1):7915. doi: 10.1038/s41598-025-91085-x.
This article presents a multi-point calibration approach for electron probe microanalysis (EPMA) for the trace element analysis of indium in sphalerite (ZnS). To define a multi-point calibration curve, indium and cadmium-doped ZnS crystals in a concentration range from 0 (blank) to ~ 1500 µg / g were used. The samples were measured with two different analytical settings (25 kV acceleration voltage and 100 nA beam current as well as 7 kV and 200 nA). The figures of merit including, beam stability, lower limit of detection and limit of quantification as well as the reproducibility and precision are assessed. Equally, the line overlap of Cd and chemical shift due to non-matrix matched standards is discussed. The multi-point calibration approach results in a 2-3 times improved analytical precision compared to the classical calibration approach using only one calibration sample, and detection limits down to about 20 µg / g were achieved.
本文介绍了一种用于闪锌矿（ZnS）中铟微量元素分析的电子探针微分析（EPMA）多点校准方法。为定义多点校准曲线，使用了铟和镉掺杂的ZnS晶体，其浓度范围从0（空白）至约1500μg/g。样品采用两种不同的分析设置进行测量（25kV加速电压和100nA束流以及7kV和200nA）。评估了包括束稳定性、检测下限和定量限以及重现性和精密度在内的品质因数。同样，还讨论了镉的谱线重叠以及由于非基体匹配标准导致的化学位移。与仅使用一个校准样品的经典校准方法相比，多点校准方法使分析精密度提高了2至3倍，并实现了低至约20μg/g的检测限。
