Influence of Iron Catalyst in the Carbon Spheres Synthesis for Energy and Electrochemical Applications

Abstract

Carbon spheres of nanometric dimension are known since the first studies on the synthesis of fullerenes. Their shape originates from the curvature of a carbon sheet similar to fullerenes, but with numerous graphitic rings that regulate the inside structure and the formation of open edges at the surface. This paper focuses on the structural and electronic characterization of carbon spheres obtained from a chemical vapor deposition synthesis process. Two different sets of samples are analyzed in detail, in particular, electron microscopies and Raman spectroscopy help understanding the morphology and the graphitic‐sp2 arrangement of the carbon atoms in the architectures. In addition, the iron catalyst used during the reaction process confers the carbon spheres a ferromagnetic response at room temperature. Therefore, both the structural properties of the samples and the active contribution of iron mark the difference in the measured photoresponse as well as in the electrochemical behavior. The X‐ray photoelectron spectroscopy study addresses these points by giving information on the composition and the iron chemical state in the assembly. The collected results underline the advantages offered by this nanomaterial for sustainable applications.

Nano-Sized Fe(III) Oxide Particles Starting from an Innovative and Eco-Friendly Synthesis Method

“…The XPS peaks of the Fe 2p3/2 and 2p1/2, for the same samples at different initial chloride concentrations, are also shown in Figure 2. A characteristic satellite peak is located approximately 8 eV higher than the main Fe 2p3/2 peak [45,46]. The binding energies of Fe 2p3/2 and Fe 2p1/2 obtained from the present study are 711.4 and 725.0 eV, respectively.…”

Functionalization of Carbon Spheres with a Porphyrin−Ferrocene Dyad

“…The CSs starting material was obtained by a CVD process and a detailed characterization of the outer and inner structure of the spheres as well as their spectroscopic properties will be reported in detail elsewhere and is here summarized …”

“…In the field of solar energy conversion, many recently published papers mainly focused on fullerenes applied to organic solar cells operating in solution and on carbon nanotubes in the solid state. In the present study, we investigated the functionalization of carbon spheres (CSs), a material recently produced in our laboratories . The functionalization was carried out with a dyad built by interconnecting a porphyrin and a ferrocene with a triple bond, as shown in Figure b.…”

Designing Cascades of Electron Transfer Processes in Multicomponent Graphene Conjugates

“…In light of our experience, [42, 44] we opted in this work for linking electron‐donating ferrocenes (Fc) with light‐harvesting/electron‐donating (metallo)porphyrins (ZnP) and electron‐accepting graphene nanoplates (GNP) via oligo‐ p ‐phenyleneethynylenes of variable lengths. A unique feature of our nanocarbon‐based materials is the β‐linkage at the (metallo)porphyrins to modulate the electron donor‐acceptor interactions.…”