摘要
样品晶粒尺寸及样品高度偏差对XRD测试结果存在极大影响。实验结果表明,晶粒尺寸过大会导致异于标准卡片的衍射峰出现,且衍射谱图不具有重现性;样品高度偏差则会导致衍射峰位移动,正高度偏差使衍射峰向高角度方向移动,负高度偏差使衍射峰向低角度方向移动,峰位移动量与高度偏差呈正比:△2θ=360cosθ/πR△h。样品晶粒和高度偏差过大以致结果异常的情况应视为制样错误,测试过程中应予重视。
Influence of sample crystal grain size and height displacement on XRD results was investigated via experimental and theoretical analysis. The results indicate that, diffraction peaks other than those on standard card would appear when grain size is too large, which makes the diffraction patterns unreliable and unreproducible. Sample height displacement would cause diffraction peak shift, positive displacement leads the peaks to higher 2theta while negative displacement leads the peaks to lower 2theta. The amount of shift is proportional to the height displacement as △2θ=360cosθ/πR△h. Abnormal results caused by large crystal grain size and heightdisplacement should not be ignored, it should be treated as seriously as sample preparation error. The results could help students understand the requirements of XRD sample preparation and provide a reference for XRD experiment teaching.
作者
肖康
王琼
苏凡
马延文
辛颢
XIAO Kang;WANG Qiong;SU Fan;MA Yan-wen;XIN Hao(School of Materials Science ＆ Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Advanced Analysis and Testing Center,Nanjing Forestry University,Nanjing 210037,China)
出处
《广州化学》
CAS
2018年第5期1-10,共10页
Guangzhou Chemistry
基金
南京邮电大学引进人才科研启动基金(NY215016)
南京邮电大学国自基金孵化项目(NY215079)
南京邮电大学教务处处控优秀课程建设基金(MOOC-2016-6)
关键词
XRD
样品制备
晶粒尺寸
高度偏差
测试误差
XRD
sample preparation
crystal grain size
height displacement
analysis error
