CAJ | 학술논문

以膨胀石墨与硅溶胶为原料制备出一种碳化硅包覆石墨材料。利用电子显微镜、X射线衍射技术、热重分析和荧光光谱技术对样品的形貌、结构、组成以及光致发光性能进行表征。结果表明，与碳化硅材料相比，碳化硅包覆石墨材料的发光频带发生红移，即由原来的蓝光红移至黄绿光，拓展了碳化硅的光致发光光谱。其原因是由于位于材料内部的石墨与外部的碳化硅之间形成的内电场阻碍了电子回归基态，从而使得光电子恢复到基态所释放的能量低于纯碳化硅释放的能量。
이팽창석묵여규용효위원료제비출일충탄화규포복석묵재료。이용전자현미경、X사선연사기술、열중분석화형광광보기술대양품적형모、결구、조성이급광치발광성능진행표정。결과표명，여탄화규재료상비，탄화규포복석묵재료적발광빈대발생홍이，즉유원래적람광홍이지황록광，탁전료탄화규적광치발광광보。기원인시유우위우재료내부적석묵여외부적탄화규지간형성적내전장조애료전자회귀기태，종이사득광전자회복도기태소석방적능량저우순탄화규석방적능량。
SiC-encapsulated graphite was prepared by carbonization of a mixture of expanded graphite and silica sol at 1 300 ℃for 6 h, heat treatment in air at 700 ℃ 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.