Preparation and crystallization of hollow α-Fe2O3 microspheres following the gas-bubble template method

L. De Los Santos Valladares, L. León Félix, S. M. Espinoza Suarez, A. G. Bustamante Dominguez, T. Mitrelias, S. Holmes, N. O. Moreno, J. Albino Aguiar, C. H.W. Barnes

Resultado de la investigación: Contribución a una revistaArtículorevisión exhaustiva

13 Citas (Scopus)


In this work we report the formation of hollow α-Fe2O3 (hematite) microspheres by the gas-bubble template method. This technique is simple and it does not require hard templates, surfactants, special conditions of atmosphere or complex steps. After reacting Fe(NO3)3.9H2O and citric acid in water by sol-gel, the precursor was annealed in air at different temperatures between 180 and 600 °C. Annealing at 550 and 600 °C generates bubbles on the melt which crystallize and oxidizes to form hematite hollow spheres after quenching. The morphology and crystal evolution are studied by means of X-ray diffraction and scanning electron microscopy. We found that after annealing at 250-400 °C, the sample consist of a mixture of magnetite, maghemite and hematite. Single hematite phase in the form of hollow microspheres is obtained after annealing at 550 and 600 °C. The crystallization and crystal size of the hematite shells increase with annealing temperature. A possible mechanism for hollow sphere formation is presented.

Idioma originalInglés
Páginas (desde-hasta)21-27
Número de páginas7
PublicaciónMaterials Chemistry and Physics
EstadoPublicada - 1 feb. 2016
Publicado de forma externa

Nota bibliográfica

Publisher Copyright:
© 2015 Published by Elsevier B.V.


Profundice en los temas de investigación de 'Preparation and crystallization of hollow α-Fe2O3 microspheres following the gas-bubble template method'. En conjunto forman una huella única.

Citar esto