X射线粉末衍射测试条件优化及分析

Analysis and Optimization of X-ray Powder Diffraction Testing Conditions

利用布鲁克D8 Discover型X射线衍射仪进行了测试条件优化研究。研究以常见的商业二氧化钛粉末(P25)为例,通过对比不同样品架选择、样品制备方法、附件选择、仪器测试参数设定等方面对获取样品衍射数据的影响。研究结果表明:选择合适材质与合适开槽大小的样品架,可避免出现样品架的背景峰;制样时,保证样品高度处于衍射中心,可避免衍射峰的偏移;添加防散射装置,并正确安装防散射装置可降低待测样品在低角度时的衍射背景峰;设置测试方法时,合适的步径和计数时间选择利于获取高质量的衍射数据。待测试样品中有微量相存在时,适当增加计数时间,利于微量相的分辨。以上实验研究结果为其他仪器操作者测试样品提供参考依据。

Optimization of the test conditions is studied using X-ray diffractometer(D8 Discover,Bruker)and commercial titanium dioxide powder(P25).In this paper,the parameters of sample holder selection,sample preparation methods,accessory selection,and instrument testing parameter settings are compared to investigate the effect on the diffraction of samples.The results show that the background peaks of the sample holder can be avoided by choosing the appropriate material and the appropriate size of the slotted sample holder.The deflection of the diffraction peaks is effectively prevented when the sample height is at the diffraction center during preparation.The addition and accurate installation of the anti-scattering device reduce the diffraction background of the sample.The appropriate step size and counting time are significant to obtain high quality diffraction data.The counting time needs to be increased appropriately to facilitate the resolution of the trace phase in the tested samples.These experimental results provide references for other instrument operators in testing their samples.