Preparation of I2@SWNTs: synthesis and spectroscopic characterization of I2-loaded SWNTs.

X-ray photoelectron spectroscopy (XPS) along with inductively coupled plasma analysis (ICP-AE) and Raman spectroscopy have been used to define the location and to quantify the amount of iodine in HiPco SWNT samples loaded with molecular I(2) via sublimation (I(2)-SWNTs). The exterior-adsorbed I(2) can be removed (as I(-)) by reducing the sample of filled nanotubes with Na(0)/THF or by heating the I(2)-SWNTs to 300 degrees C (without reduction), leaving I(2) contained only within the interior of the SWNTs (I(2)@SWNTs) as proven by XPS. These I(2)@SWNTs contain approximately 25 wt % of I(2) and are stable without the loss of I(2) even after exposure to additional reduction with Na(0)/THF or upon heating to ca. 500 degrees C.