Preparation and characterization of yellow-green fluorescence emitting SiC-encapsulated graphite

SiC-encapsulated graphite was prepared by carbonization of a mixture of expanded graphite and silica sol at 1300 °C for 6 h, heat treatment in air at 700 °C for 4 h to remove unreacted surface carbon and HCl-HF etching to remove silica. XRD, TGA, TEM and SEM were used to characterize the samples. Results indicated that the fluorescence emission of the SiC-encapsulated graphite shifts from blue to yellow-green light compared to pure SiC. This might be caused by a built-in potential near the junction between graphite and SiC, which makes the energy of the photogenerated electron released while returning to ground state lower than that of pure SiC. arbon Materials 2014, 29(5): 404–408]