碲化镉溶液中无机痕量杂质成分分析标准物质研制

本文研制了2 mg/g碲化镉（CdTe）溶液中无机痕量杂质成分分析的5种标准物质，每种包含21种杂质元素，浓度分别为0、1、2、4、8 ng/g。通过辉光放电质谱（GD-MS）法对CdTe原料纯度进行测量，筛选得到纯度>99.999%的高纯原料；使用HCl-HNO₃混酸将其溶解，再根据成分设计定量添加杂质元素，制备得到标准物质候选物。建立了基体匹配-内标校正-电感耦合等离子体质谱法用于标准物质定值与均匀性、稳定性检验，采用标准物质EB507验证方法可靠性。对包装容器溶出进行考察，以高密度聚乙烯（HDPE）作为包装容器可满足要求。采用建立的方法对全部元素进行检验，结果表明，标准物质均匀性以及长、短期稳定性良好，有效期12个月。通过8家实验室联合定值的方式，对标准物质中21种元素进行定值，以算数平均值作为标准值，并对不确定度进行全面、系统地评估。该系列基体标准物质填补了国内外空白，对于验证测量方法的可靠性、确保测量结果的一致性与溯源性具有重要作用。

Development of Reference Materials for the Analysis of Inorganic Trace Impurities in Cadmium Telluride Solutions

A series of matrix reference materials for 21 inorganic trace impurities in 2 mg/g cadmium telluride (CdTe) solution with five impurity concentration levels (0, 1, 2, 4, 8 ng/g) were developed. High purity (>99.999%) CdTe was used as raw materials and dissolved using HCl-HNO₃ mixed acid, and then was doped with multi-elements solutions to prepare the candidate reference materials (RMs). Matrix-matched ICP-MS with internal standard calibration was established for certification, homogeneity test and stability test. Mass spectrum interferences of ¹⁰⁶Cd¹H on ¹⁰⁷Ag and ¹¹⁴In¹H on ¹¹⁵In could be effectively removed by optimizing argon gas flow parameters coupled with mathematical correction. The matrix suppressed effect was effectively corrected about 20%-60% by using matrix-matched method. The precision of consecutive analysis expressed as RSD (n=22) was reduced to approximately 1% by using internal standard calibration. The linearly correlation coefficient factors (R) of standard curves were greater than 0.999 for all elements. The limits of detection (LODs) ranged from 0.001 ng/g to 0.35 ng/g, and the spike recoveries ranged from 89.2% to 106.5%. The established method was further validated by using CRM EB507. The dissolution of packaging containers was investigated and the results showed that the impurity dissolution from HDPE (high density polyethylene) bottle was lower than that from PP (polypropylene) plastic bottle. Except for Ca and Se, the dissolution of elements of concern in 4 months was less than 0.2 ng/g, which met the requirement. All elements were tested by the established method, and the results showed that the homogeneity, long-term and short-term stability of RMs were satisfactory and the validity period was 12 months. The mass fractions of 21 elements were certified by using a collaborative characterization program with eight sophisticated participating laboratories and using HR-ICP-MS and Q-ICP-MS methods. The arithmetic mean values were taken as the certified values, and the uncertainty was systematically and comprehensively evaluated. The measured results ranged from 3.5 ng/g to 4.5 ng/g, and the RSD ranged from 1.2% to 8.5% from 8 labs. The average value was about 4.0 ng/g, which was consistent with the target values and the relative expanded uncertainty was about 7%. This series of matrix RMs fills the blank of relevant RMs at home and abroad, and it plays an important role in verifying the reliability of measurement methods and ensuring the consistency and traceability of measurement results.