Core/Shell Structure of Ni/NiO Encapsulated in Carbon Nanosphere Coated with Few- and Multi-Layered Graphene: Synthesis, Mechanism and Application

Abstract

This paper focuses on the synthesis and mechanism of carbon nanospheres (CNS) coated with few-and multi-layered graphene (FLG, MLG). The graphitic carbon encapsulates the core/shell structure of the Ni/NiO nanoparticles via the chemical vapor deposition (CVD) method. The application of the resulting CNS and hybrids of CNS-FLG and CNS-MLG as reinforcement nanofillers in a polypropylene (PP) matrix were studied from the aspects of mechanical and thermal characteristics. In this research, to synthesize carbon nanostructures, nickel nitrate hexahydrate (Ni(NO 3 ) 2 ·6H 2 O) and acetylene (C 2 H 2 ) were used as the catalyst source and carbon source, respectively. Besides, the morphology, structure and graphitization of the resulting carbon nanostructures were investigated. On the other hand, the mechanisms of CNS growth and the synthesis of graphene sheets on the CNS surface were studied. Finally, the mechanical and thermal properties of the CNS/PP, CNS-FLG/PP, and CNS-MLG/PP composites were analyzed by applying tensile test and thermogravimetric analysis (TGA), respectively.

One-step synthesis of carbon nanospheres with an encapsulated iron-nickel nanoalloy and its potential use as an electrocatalyst

“…Then, acetylene flowing into the reactor at 2.0 ml min −1 for 20 min to synthesize the CNSs was used. In agreement with Ghaemi et al [19], once started the pyrolysis of the acetylene, the resultant carbon atoms diffuse to the surface of the catalytic nanoparticles. After reaching the carbon-solubility limit, carbon precipitates out and crystallizes to form a graphitic structure that surrounds the metal, obtaining metallic nanoparticles encapsulated by CNSs.…”

One Pot Synthesis, Surface, and Magnetic Properties of Ni–NiO@C Nanocomposites

“…Contrarily, carbon nanocomposite products containing metal nanoparticles such as copper and cobalt, as well as nickel or its oxides, are an excellent substitute for use in a wide range of applications involving magnetic resonance tomography and biomedicine, electrode materials over super capacitors, heterogeneous catalysts for petrochemical processes, and dispersed radiation-absorbing media [22]. A core/shell structure of Ni-NiO, encapsulated in carbon nanospheres (CNS) and coated with few-and multi-layered graphene (FLG and MLG) was prepared using the chemical vapor deposition (CVD) method [23]. Carbon atoms were first placed on the Ni particle surface, which initiated the process.…”

Large exchange bias and enhanced coercivity in strongly-coupled Ni/NiO binary nanoparticles

“…These factors are critical especially in nanosized crystals and are strongly affected by the synthetic route. Remarkable progress has been made in recent years regarding the synthesis of the Ni/NiO binary manoparticles., 10,12,[17][18][19][20] Highly crystalline and monodisperse Ni/NiO nanoparticles have been prepared by the physical techniques including laserinduced reductive sintering, 3 sequential layer deposition, 10 CVD method, 21 nanosecond laser irradiation, 22 cluster-beam deposition, 23 and pulsed laser deposition. 24 However, universal agreement of the origin of the EB effect and other related anomalous magnetic properties is still under debate.…”