二氧化硅颗粒堆积空隙中氢气分子的核磁共振谱学特征研究  

Studies on the^(1)H NMR Spectral Features of Hydrogen Molecules in the Interstices of SiO2 Particles

作　　者：王行乐 邵正泽 董洪春 魏达秀[1] 陈群[1] 姚叶锋[1] WANG Xingle;SHAO Zhengze;DONG Hongchun;WEI Daxiu;CHEN Qun;YAO Yefeng(Shanghai Key Laboratory of Magnetic Resonance,College of Physics and Electronic Science,East China Normal University,Shanghai 200062,China)

机构地区：[1]上海市磁共振重点实验室,物理与电子科学学院,华东师范大学,上海200062

出　　处：《波谱学杂志》2024年第3期315-321,共7页Chinese Journal of Magnetic Resonance

基　　金：上海市科委“科技创新行动计划”项目(22142200800).

摘　　要：本文研究了一系列不同尺寸二氧化硅小球堆积空隙中氢气分子的核磁共振信号特征,观察到氢气分子化学位移随着小球堆积空隙尺寸减小逐渐向高场变化的现象.结合变温氢谱、氢气自扩散系数测量及扫描电镜等实验结果,认为两个因素的共同作用是该现象产生的原因,即:1)抗磁性的二氧化硅小球所导致的磁场不均匀性分布随小球尺寸变化而变化;2)处在小球空隙内不同位置的氢气分子间存在快速交换.本文结果展示了氢气作为探针分子用于微纳空隙尺寸测量的可能性.^(1)H NMR spectral features of hydrogen molecules in the stacking interstices of silicon dioxide(SiO_(2))microspheres with different sizes are studied in the present article.The chemical shift of hydrogen molecules is observed to gradually shift towards higher fields as the size of the stacking interstices decreases.Combined with experimental results of variable temperature hydrogen spectroscopy,self-diffusion coefficients measurement,and scanning electron microscopy,the observed phenomenon is attributed to two factors,namely,1)the microsphere size-dependent local magnetic field inhomogeneity in the stacking interstices caused by the diamagnetic SiO_(2) microspheres;and 2)the rapid exchange among hydrogen molecules experiencing different local fields within the microsphere interstices.The results of this study demonstrate the potential of hydrogen gas as a probe molecule for measuring micro-and nano-scale pore sizes.

关 键 词：氢气 二氧化硅 堆积空隙 核磁共振 化学位移 

分 类 号：O482.53[理学—固体物理]