Advanced Materials: TechConnect Briefs 2015Advanced Materials TechConnect Briefs 2015

Nanoscale Materials Characterization Chapter 1

Raman Spectroscopic Characterization of Carbon Nanotubes & Tungsten Oxide of Relevance to Energy Storage and Gas Sensing Applications

P. Misra, D. Casimir, R. Garcia-Sanchez, S. Baliga
Howard University, United States

pp. 55 - 58

Keywords: Raman spectroscopy, carbon nanotubes, tungsten oxide

The characterization of graphitic and metal oxide nanomaterials through the use of Resonant Raman Spectroscopy at multiple laser excitations is the primary aim of this research. Raman spectroscopic techniques can help characterize the vibrational phonon modes of nano-materials with little in the way of sample preparation, making it an ideal tool for device characterization. The Stokes Raman spectra of carbon nanotubes and tungsten oxide were recorded with a DXR Smart Raman spectrometer over a temperature range of 27-200 degrees Celsius. The Raman spectra of SWCNTs were used to demonstrate the bond softening and resultant red-shifting of the various Raman peaks of SWCNTs. The thermal changes in the spectra were used to characterize the nanomaterial samples with an eye to future applications for energy storage (using carbon nanotubes) and for toxic gas sensing (using tungsten oxide). The observed and modeled red-shifting of the Raman frequencies and broadening of the peak widths are being used to better understand the thermo-mechanical response of the nanomaterials for potential device applications at elevated temperatures.