Nanoparticle size, oxidation state, and sensing response of tin oxide nanopowders using Raman spectroscopy

作者：Vijayarangamuthu K; Rath Shyama^*

来源：Journal of Alloys and Compounds, 2014, 610: 706-712.

DOI：10.1016/j.jallcom.2014.04.187

• Tin oxide
• Sol-gel
• Nanostructured materials
• Raman spectroscopy
• Optical sensing

Tin oxide nanopowders were prepared by a sol-gel method and annealed at different temperatures in an oxygen atmosphere. The amorphous-to-crystalline transformation, the evolution of the nanocrystals, the sizes and their distribution, the surface characteristics, and the degree of oxidation as a function of annealing temperature are all determined from the Raman spectra. The changes in the Raman spectra between 100 and 200 cm(-1) represent the change in the oxidation state. The A(1g) mode, which is a signature of a crystalline SnO2 phase, is used to determine the nanocrystal sizes. The Raman spectra clearly reveal the gradual transformation of Sn(OH)(2) to SnOx and ultimately to SnO2 with annealing. The crystallinity and crystallite sizes are also confirmed with X-ray diffraction and transmission electron microscopy measurements. Furthermore, Raman spectroscopy is utilized to study the sensing response of the thus synthesized SnOx to NH3 gas and 2-nitrophenol. Raman spectroscopy is thus demonstrated to be a rapid and comprehensive technique to determine a multitude of parameters of tin oxide relevant for sensing applications.

• 出版日期2014-10-15