Chemical Engineering Program, Arizona State University, Tempe, AZ 85287, United States.
J Colloid Interface Sci. 2012 Dec 1;387(1):127-34. doi: 10.1016/j.jcis.2012.06.062. Epub 2012 Jul 6.
Mesoporous carbons containing cobalt nanoparticles are synthesized by tri-or quad-constituent self assembly of Pluronic F127, phenol-formaldehyde oligomer (resol), cobalt acetylacetonate (acac), and optionally tetraethyl orthosilicate (TEOS, optional). Upon pyrolysis in N(2) atmosphere, the resol provides sufficient carbon yield to maintain the ordered structure, while decomposition of the Co(acac) yields cobalt nanoparticles. To provide increased surface area, the dispersed silicate from condensation of TEOS can be etched after carbonization to yield micropores, Without silica templated micropores, the surface area decreases as the cobalt content increases, but there is a concurrent increase in the volume-average pore diameter (BHJ) and a dramatic increase in the adsorption capacity of methylene green with the equilibrium adsorption capacity from 2 to 90 mg/g with increasing Co content. Moreover, the surface area and pore size of mesoporous composites can be dramatically increased by addition of TEOS and subsequent etching. These composites exhibit extremely high adsorption capacity up to 1151 mg/g, which also increases with increases in the Co content. Additionally, the inclusion of cobalt nanoparticles provides magnetic separation from aqueous suspension. The in situ synthesis of the Co nanoparticles yields to a carbon shell that can partially protect the Co from leaching in acidic media; after 96 h in 2 M HCl, the powders remain magnetic.
介孔碳载钴纳米粒子是通过三或四元自组装 Pluronic F127、酚醛低聚物（Resol）、乙酰丙酮钴（Acac）和任选的正硅酸乙酯（TEOS，可选）合成的。在 N2 气氛下进行热解时，Resol 提供了足够的碳产率来维持有序结构，而 Co（Acac）的分解则产生了钴纳米粒子。为了提供更高的比表面积，碳化后可以刻蚀分散的硅来自于 TEOS 的缩合以产生微孔。没有二氧化硅模板的微孔时，随着钴含量的增加，比表面积减小，但体积平均孔径（BHJ）增加，亚甲基蓝的吸附容量也显著增加，平衡吸附容量从 2 到 90mg/g 随钴含量的增加而增加。此外，通过添加 TEOS 和随后的刻蚀可以显著增加介孔复合材料的比表面积和孔径。这些复合材料表现出极高的吸附容量，高达 1151mg/g，并且随着钴含量的增加而增加。此外，钴纳米粒子的包含提供了从水悬浮液中进行磁性分离的能力。Co 纳米粒子的原位合成导致了碳壳的形成，该碳壳可以部分保护 Co 免受酸性介质中的浸出；在 2M HCl 中 96 小时后，粉末仍保持磁性。
