LiCl／γ—Al2O3的^7LiMASNMR研究  

~7Li MAS NMR Studies on LiCI/γ-Al_2O_3

作　　者：王凯旋[1] 杨夏万[1] 赵璧英[1] 谢有畅[1] 孙平川[2] 门爱菊[2] 

机构地区：[1]北京大学物理化学研究所,北京100871 [2]南开大学高分子化学研究所,天津300071

出　　处：《物理化学学报》1997年第3期196-199,共4页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金;南开大学功能高分子国家重点实验室资助

摘　　要：A Series of LiCl/γ-Al2O3 samples were prepared by mixing and then heating at 400℃ for 30 hours. 7Li MAS NMR was used to investigated their structures. The 7Li MAS NMR signal of LiCl in the dispersion phase was observed for the first time, and its chemical shift was at 0.25ppm.After the dispersion threshold of LiCl on γ-Al2O3 was achieved, the 7Li signal in the crystallme phase LiCl appears at -1.01ppm and its intensity increases with the increasing in LiCl loading.From the 2D nutation NMR spectra, it can be seen that the electric field gradient surrounding the lithium nuclei in the dispersion state is larger and so the quadrupole interaction is stonger than that in the crystalline state. The dispersion threshold indicated by NMR is in agreement with that deduced from XRD, which is about 0.136gLiCl/gγ-Al2O3.A Series of LiCl/γ-Al2O3 samples were prepared by mixing and then heating at 400℃ for 30 hours. 7Li MAS NMR was used to investigated their structures. The 7Li MAS NMR signal of LiCl in the dispersion phase was observed for the first time, and its chemical shift was at 0.25ppm.After the dispersion threshold of LiCl on γ-Al2O3 was achieved, the 7Li signal in the crystallme phase LiCl appears at -1.01ppm and its intensity increases with the increasing in LiCl loading.From the 2D nutation NMR spectra, it can be seen that the electric field gradient surrounding the lithium nuclei in the dispersion state is larger and so the quadrupole interaction is stonger than that in the crystalline state. The dispersion threshold indicated by NMR is in agreement with that deduced from XRD, which is about 0.136gLiCl/gγ-Al2O3.

关 键 词：活性组分 自发单层分散 载体表面 氯化锂 氧化铝 

分 类 号：O647.2[理学—物理化学]