Synthesis and characterization of magnetic Co nanoparticles: A comparison study of three different capping surfactants
Synthesis and characterization of magnetic Co nanoparticles: A comparison study of three different capping surfactants
复制标题
DOI：
10.1016/j.jssc.2008.02.016
复制
发表时间：
2008-07-01
影响因子：
3.3
通讯作者：
Xia, Younan
中科院分区：
文献类型：
--
作者：
Lu, Yu;Lu, Xianmao;Xia, Younan
本文比较了三种长链酸--油酸和油酸酯（均为油酸）和硬脂酸酯（均为脂肪酸）作为封端剂在磁性钴纳米粒子合成中的性能。该颗粒是通过八羰基二钴在甲苯中在长链酸的存在下热分解而形成的。并通过TEM，高分辨率TEM进行表征。SQUID测量红外光谱分析表明，加入的部分烯酸发生了顺式向反式构型的转变（油酸）或反式向顺式构型的转变（油酸），有利于在CO纳米颗粒表面形成致密的单分子层结构。与脂肪酸相比，由于顺式异构体的弯曲形状，烯属酸对于具有高表面曲率的致密填充油小颗粒是有利的。烯属酸的存在能够控制颗粒生长。稳定胶体悬浮液。并防止最终产品被空气氧化。我们的研究结果表明，油酸。反油酸并且油酸/硬脂酸或油酸/硬脂酸的混合物在用作具有球形形状和窄尺寸分布的Co纳米颗粒的合成的封端剂方面具有大致相同的性能。(C)2008年爱思唯尔公司All rights reserved.
This paper compares the performance of three long-chain acids-oleic and elaidic (both olcfinic) and stearic (aliphatic)-as a capping agent ill the Synthesis of magnetic Co nanoparticles. The particles were formed through thermal decomposition of dicobalt octacarbonyl in toluene in the presence of the long-chain acid. and characterized by TEM, high-resolution TEM. and SQUID measurements. Infrared spectra revealed that Some of the added olefinic acid was transformed from cis- to trans-configuration (for oleic acid) or from trans- to cis- (for elaidic acid) to facilitate the formation of a densely packed monolayer It on the surface of CO nanoparticles. As compared to aliphatic acids, olefinic acids are advantageous for dense packing oil small particles with high surface curvatures due to a bent shape of the cis-isomer. The presence of an olefinic acid is able to control particle growth. stabilize the colloidal suspension. and prevent the final product from oxidation by air. Our results indicate that oleic acid. elaidic acid. and a mixture of oleic/stearic acids or elaidic/stearic acids have roughly the same performance in serving as a capping agent for the Synthesis of Co nanoparticles with a spherical shape and narrow size distribution. (C) 2008 Elsevier Inc. All rights reserved.