Design of Cobalt Nanoparticles with Tailored Structural and Morphological Properties via O/W and W/O Microemulsions and Their Deposition onto Silica

Catalysts

Gabriella Di Carlo⁴  Matteo Lualdi¹  Anna M. Venezia³  Magali Boutonnet¹  Margarita Sanchez-Dominguez² 

[1] Division of Chemical Technology, Department of Chemical Engineering and Technology, Royal Institute of Technology (KTH), Teknikringen 42, 10044, Stockholm, Sweden; E-Mails:;Centro de Investigación en Materiales Avanzados, S. C. (CIMAV), Unidad Monterrey, Alianza Norte 202, 66600 Apodaca, Nuevo León, Mexico;Istituto per lo Studio dei Materiali Nanostrutturati (ISMN)–CNR, via Ugo La Malfa 153, 90146, Palermo, Italy; E-Mail:;Istituto per lo Studio dei Materiali Nanostrutturati (ISMN)−CNR, Via Salaria Km 29.3, 00015, Monterotondo, Roma, Italy; E-Mail:

关键词: cobalt nanoparticles;    cobalt oxide;    microemulsions;    nano-reactor;    silica support;   

DOI  :  10.3390/catal5010442

来源: mdpi

【 摘 要 】

Cobalt nanostructures with different size and morphology, i.e., spherical nanoparticles, nanorods, and particles arranged into elongated structures, were prepared using micelles and microemulsions as confined reaction media. The syntheses were carried out using three types of systems: aqueous surfactant solutions, oil-in water (O/W), and water-in-oil (W/O) microemulsions. The influence of the surfactant and the precipitating agent used for synthesis was also investigated. For this purpose, cobalt nanostructures were prepared using different non-ionic surfactants, namely Synperonic^® 10/6, Pluronic^® P123 and a mixture of SPAN 20–TWEEN 80. Three different precipitating agents were used: sodium borohydride, sodium hydroxide, and oxalic acid. Our findings revealed that by changing the type of reaction media as well as the precipitating agent it is possible to modify the shape and size of the cobalt nanostructures. Moreover, the use of O/W microemulsion generates better results in terms of colloidal stability and uniformity of particle size with respect to W/O microemulsion. The different cobalt nanostructures were supported on commercial and mesoporous silica; transmission electron microscopy (TEM) images showed that after deposition the Co nanocrystals remain well dispersed on the silica supports. This behavior suggests their great potential in catalytic applications.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.