Synthesis and Characterization of Carbon-Encapsulated Nickel Nanoparticles from De-Oiled Asphalt
Carbon-encapsulated Ni nanoparticles with the size of 5 to 30 nm were synthesized from de-oiled asphalt (DOA) by heat-treatment at 1800 °C with nickel powder. The nanoparticles exhibited well-constructed core-shell structures, with Ni cores and graphitic shells. High resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) examinations confirmed that the carbon-encapsulated Ni nanoparticles were uniformly dispersed in carbon matrix and the Ni nanoparticles were surrounded by several carbon layers with well ordered arrangement. The formation of the core-shell nanoparticles was selectively controlled by adjusting the ratio of de-oiled asphalt to nickel powders. The possible growth model for the carbon-encapsulated Ni nanoparticles was discussed briefly. This result presents a simple and controllable way to synthesize carbon-encapsulated nickel nanoparticles.
Zhengyi Jiang, Xianghua Liu, Sihai Jiao and Jingtao Han
J. Yu and B. S. Xu, "Synthesis and Characterization of Carbon-Encapsulated Nickel Nanoparticles from De-Oiled Asphalt", Advanced Materials Research, Vols. 652-654, pp. 202-205, 2013