材料期刊网

Pt与Au的原子序数相近，X射线激发下，影响它们荧光强度的诸多因素都非常相近，据此建立了利用金首饰系列标准物质（只含Au、Cu元素）和Pt、Cu峰面积修正，X射线荧光光谱法（XRF ）测定铂首饰样品（只含Pt、Cu元素）中Pt 含量的分析方法。首先，通过测定金首饰系列标准物质，绘制Cu含量（wCu ）与Cu、Au峰面积比值Q（ICu／IAu ）之间的校准曲线；其次，通过试验对铂首饰标准物质的Pt和Cu的峰面积进行修正，并计算其Q值；最后，采集铂首饰样品的谱图，求Q值，查校准曲线，即可求出铂首饰中的Cu含量，进而间接计算出Pt的含量。方法适用于铂质量分数为91.70％～99.92％的铂首饰的测定。对5件铂首饰样品进行测定，结果与原子吸收光谱法（AAS）一致。实验方法解决了测定铂首饰中的铂时缺乏铂标准样品的难题。

The atomic number of Pt and Au was close .As a result ,many factors influencing the fluores‐cence intensity were also close under X‐ray excitation .The analysis method of Pt content in Pt jewelry (only containing Pt and Cu) by X‐ray fluorescence spectrometry (XRF) was established after peak area correction of Pt and Cu using Au jewelry serials certified reference materials (only containing Au and Cu) . Firstly ,the Au jewelry serials certified reference materials was determined to prepare the calibration curve between Cu content (wCu ) and Cu/Au peak area ratio Q(Q= ICu/IAu ) .Secondly ,the peak areas of Pt and Cu in Pt jewelry certified reference materials were corrected by experiments to calculate the value of Q .Fi‐nally ,the spectra of Pt jewelry samples were collected to calculate the value of Q .The content of Cu in Pt jewelry could be obtained based on calibration curve .Then ,the content of Pt could be indirectly calculat‐ed .The proposed method was applicable for the determination of Pt jewelry with Pt content of 91.70%‐99.92% .Five Pt jewelry samples were determined according to the experimental method ,and the found results were consistent with those obtained by atomic absorption spectrometry (AAS) .The proposed method solved the problem in lack of Pt certified reference materials during the determination of Pt in Pt jew elry .