摘要
使用“柠檬酸法”制备了一系列较高比表面的W-Fe-MgO催化剂,在较易放大的流化床反应器中,1100℃H_2气流中分解CH_4,制得SWCNTs管束,单管直径在1～3nm,最高碳产率36mg/100mg催化剂。经TEM、微区Raman、程序升温氧化(TPO)测量表明,产物中无定形碳、MWCNTs均较少,为纯度较高、缺陷较少的SWCNTs。从EDAX结果并参考W-Fe相图推测SWCNTs生长的催化剂活性相可能为W、Fe的金属间化合物或富Fe的固溶体。
A series of W-Fe-MgO catalysts with high BET surface area were prepared by mixing Mg(NO3)(2) . 6H(2)O, ammonium tungstate, citric acid, Fe(NO3)(3) . 9H(2)O and H2O, followed by drying at 150 degreesC and decomposing at 550 degreesC. Using these catalysts, bundled SWCNTs with diameter 1 similar to 3 nm for each tube, were synthesized in a fluidized reactor. The maximum yield of SWCNTs was 36 mg/100 mg. TEM, micro-Raman and TPO (temperature programmed oxidation) results showed that the products were SWCNTs of high purity and almost defect-free. From the EDAX results and phase-diagram of W-Fe, we deduced that the active phase for SWCNTs growth was a solid solution or an intermetal compound of tungsten and iron.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2003年第11期1093-1096,共4页
Acta Physico-Chimica Sinica
基金
国家重点基础研究发展规划(G2000077503)
国家自然科学基金(20273003)~~
