[Study on Raman spectra of multi-walled carbon nanotubes with different parameters].

In order to study the influencing factors on Raman spectroscopy, we research a series of comparative Raman spectroscopy of multi-walled carbon nanotubes (MWCNT) with different tube diameter and length. The results suggest that the G peak and D peak of MWCNT are all red-shifted as compared to that of polycrystalline graphite; In the same conditions, the peak intensity (G peak and D peak) is directly proportional to the diameter of the MWCNT, and inversely proportional to the length of the MWCNT; G peak frequency shift is closely related to the MWCNT diameter and length, which are inversely proportional to the diameter (with identical results of the single-walled carbon nanotube radial breathing modes) and direct proportional to the length. While, the influences of the diameter and length on D peak frequency shift are weak, and future analysis for the reason of this kind of phenomenon is as follows.

[Raman spectrum study on synthesis mechanism of porous ZnO microspheres assisted with trisodium citrate].

Raman spectrum was applied to analyze the synthesis mechanism of nanostructure porous ZnO microspheres prepared via hydrothermal method assisted with trisodium citrate. The Raman spectrum characteristics of the sample revealed that the ZnO microspheres contained Zn-citrate complex, which was the complex of citrate acid group and Zn2+ in the reaction solution. The complex was chemisorbed on (204) and (503) faces of the Zn(OH)2 crystallite in the reacting solution, resulting in Zn(OH)2 nanosheet from the crystallite.