Stability of fullerenes under hydrothermal conditions

Abstract

Stability of fullerenes C60 under hydrothermal conditions (200–800 °C, 100 MPa, 20 min–168 h) has been investigated. The reaction products have been characterized by Raman spectroscopy and x-ray diffraction. The fullerenes were stable up to 500 °C, but they decomposed immediately at 800 ±C into amorphous carbon. In the transition region between 600 and 750 °C, longer times and higher temperatures of the hydrothermal treatment favored decomposition of C60 with the formation of amorphous carbon. Addition of nickel to the C60–H2OO system neither suppressed hydrothermal decomposition of C60 nor induced formation of other phases, except of the amorphous carbon.