太西煤及其煤基活性炭制备纳米碳化硅的比较

COMPARISON BETWEEN NANO SILICON CARBIDE MADE FROM TAIXI COAL AND ITS COAL-BASED ACTIVATED CARBON

以太西煤及其煤基活性炭为碳源,硅酸钠为硅源,Fe(NO_3)_3·9H_2O为催化剂,利用溶胶-凝胶法经碳热还原制备碳化硅粉体,探究不同n(Fe)∶n(Si)对制备的碳化硅的结构和形貌的影响.分别采用XRD,SEM和BET等分析技术对所制备的样品进行表征.结果表明,以太西煤为碳源,制得的碳化硅存在不同程度的堆积缺陷,且随着n(Fe)∶n(Si)的提高,堆积缺陷逐渐减弱,碳化硅的形貌由部分晶须逐渐变为尺寸均匀的纳米颗粒.以煤基活性炭为碳源制备的碳化硅堆积缺陷较弱,碳化硅的结晶度高,而且随着n(Fe)∶n(Si)的提高,碳化硅粒径逐渐增大,但基本保持在50nm^100nm范围.

Using Taixi coal and coal-based activated carbon as carbon source, sodium silicate as silicon source and Fe （NO3）3·9H2O as catalyst, nano-silicon carbide powder was produced by sol-gel method via carbonthermal reduction way. The effect of n（Fe） ： n（Si） on the crystal phase and morphology were researched by means of XRD, SEM and BET. The results showed that, the stacking faults of SiC decreased with the increasing value of n（Fe） ： n（Si） when using Taixi coal as coal source and the morphology of SiC changed from partial whisker to nanoparticles in the meantime. On the other hand, when using coal-based activated carbon as carbon source, all the silicon carbide produced had a weaker stacking fault relatively and its size increased slightly when the value of n（Fe） ： n（Si） increased and its grain size maintained between 50 nm-100 nm.