Synthesis, structure and porosity analysis of microporous mesoporous carbon derived from zirconium carbide

Many applications of porous carbons demand control of pore size and its distribution. One of the most promising ways to mass-produce carbon with the desired porosity is by etching of non-carbon species from inorganic carbon containing materials, such as metal carbides. In this work, carbon was synthesized from zirconium carbide, ZrC0.98, in a chlorine environment in the temperature range of 200-1200 degrees C. Thermodynamic simulation shows the possibility of carbon formation in a broad range of temperature. The structure of the resultant carbon analyzed using Raman spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM), shows that ordering of carbon took place with increase in synthesis temperature. Porosity analyzed using gas sorption technique shows that carbon produced at low temperature (300-600 degrees C) has small pores with narrow pore size distribution; whereas carbon produced at high temperature (800-1200 degrees C) has large pores with wider pore size distribution. In comparison with other carbide derived carbons, B4C and Ti3SiC2, whose pore size and its distribution do not change appreciably in 200-1000 degrees C range; carbon produced from ZrC can have both narrowly distributed micropores and mesopores depending upon the temperature of synthesis. As in carbons produced from other carbides, both the structure and porosity were found to depend on the synthesis temperature. (c) 2005 Elsevier Inc. All rights reserved.