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采用成核晶化隔离法将Co2+引入层状双金属氢氧化物(LDHs),得到了含不同Co2+/Al3+物质的量的比为1∶1,2∶1,3∶1的二元钴铝碳酸根型LDHs(CoAl-LDHs)。通过X射线衍射(XRD)、透射电镜(TEM)、扫描电镜-能量散射谱(SEM-EDS)、拉曼光谱(Raman)、程序升温还原(TPR)及X射线光电子能谱(XPS)等方法对CoAl-LDHs焙烧产物的结构、组成及其化学气相沉积(CCVD)催化生长多壁碳纳米管(CNTs)进行了研究。结果表明:CoAl-LDHs前体中钴的含量可以明显改变焙烧产物的组成分布和还原性能,并最终影响CNTs的生长,其中以nCo2+/nAl3+比为2/1的LDHs作为催化剂前体可以得到管径均匀和石墨化程度高的CNTs,这与还原得到的纳米活性Co颗粒均匀分散有关。
Co2 + was introduced into lamellar bimetallic hydroxide (LDHs) by nucleation crystallization isolation method to obtain binary cobalt aluminum with different Co2 + / Al3 + molar ratios of 1: 1, 2: 1 and 3:1 Carbonate type LDHs (CoAl-LDHs). The microstructure and mechanical properties were characterized by XRD, TEM, SEM-EDS, Raman, TPR and XPS. The structure, composition and chemical vapor deposition (CCVD) of CoAl-LDHs calcined product were studied to catalyze the growth of multi-walled carbon nanotubes (CNTs). The results show that the content of cobalt in CoAl-LDHs precursors can significantly change the compositional distribution and reduction performance of the calcined products, and ultimately affect the growth of CNTs. In the case of LDHs with nCo2 + / nAl3 + ratio 2/1 as catalyst precursors, Uniform diameter and high degree of graphitization CNTs, which is related to the uniform dispersion of the nano-active Co particles obtained by reduction.