Preparation of I2@SWNTs: Synthesis and Spectroscopic Characterization of I2-Loaded SWNTs

Abstract

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 I₂ via sublimation (I₂-SWNTs). The exterior-adsorbed I₂ can be removed (as I^-) by reducing the sample of filled nanotubes with Na⁰/THF or by heating the I₂-SWNTs to 300 °C (without reduction), leaving I₂ contained only within the interior of the SWNTs (I₂@SWNTs) as proven by XPS. These I₂@SWNTs contain ∼25 wt % of I₂ and are stable without the loss of I₂ even after exposure to additional reduction with Na⁰/THF or upon heating to ca. 500 °C.