Date of Award
Master of Science
Professor Yang Song
Tin dioxide (SnO2) nanowires and nanobelts were compressed in a diamond anvil cell to around 40 gigapascal (GPa) at room temperature followed by decompression. Raman spectroscopy was employed to monitor the pressure effect on the SnO2 nanobelts. Synchrotron X-ray powder diffraction measurements were also carried out on both nanomaterials during both compression and decompression. The diffraction patterns were analyzed quantitatively by the Rietveld refinement. Pressure-induced phase transformations were observed in both nanomaterials and compared with those observed previously in the bulk materials. However, transition pressures, phase abundances, reversibilities, as well as compressiblities were found to be different from those of the bulk materials in both nanomorphologies. The mechanisms attributed to these differences were discussed. Finally, scanning electron microscopy (SEM) images of nanobelts and nanowires were collected before compression and after decompression. Morphologies were found to be significantly altered by high pressures, providing insight into these pressure-induced transformations
Dong, Zhaohui, "HIGH-PRESSURE STUDY OF NANOSTRUCTURED SnO2 BY RAMAN SPECTROSCOPY AND X-RAY DIFFRACTION WITH SYNCHROTRON RADIATION" (2008). Digitized Theses. 4336.