Characterization of the dependence on temperature of the formation of carbon film on the internal surfaces of SBA-15 silica

The dependence of pore size of carbon-coated ordered channels of mesoporous SBA-15 on temperature is reported for the first time from characterization of as-synthesized SBA-15 after graphitization under nitrogen at relatively high temperatures. The pore sizes of the obtained products changed, respectively, from 6.8 to 7.9 and 7.3 nm, corresponding to graphitization temperature of 800-600 and 500degreesC. The formation of carbon from the template acts as a framework support that reduces the shrinkage of the pores when as-synthesized SBA-15 is heat treated at high temperature under nitrogen, resulting in materials with larger pores than in calcined SBA-15. Thus, adjusting the heat-treating temperature can control the pore size of the resultant carbon-coated samples. This is likely to play an important role in its potential use as adsorbents or in electrochemistry. (C) 2004 Published by Elsevier B.V.