Synthesis of High Surface Area, Water-Dispersible Graphitic Carbon Nanocages by an in Situ Template Approach

Abstract

This study reports an approach for synthesis of graphitic carbon nanocages (CNCs) via pyrolysis of ethanol with dissolved iron carbonyl at temperatures from 600 to 900 °C. The in situ formed Fe catalyst and template enabled the in situ generation of carbon from ethanol and formation of graphitic layers on the template surface. With the removal of the template, hollow CNCs were obtained to have a fine size of 30−50 nm and a large surface area of 400−800 m2/g. The CNCs also became dispersible in water without aggregation and settling after several months through HNO3 treatment. As an example for potential applications, the CNCs were demonstrated to be a good material for supporting the Pt catalyst used in low-temperature fuel cells. Considering its continuous and low-temperature operation, in situ formation of catalyst and template, and in situ graphitization of decomposed carbon, the present approach may be suitable for large-scale production of high surface area and water-dispersible graphitic carbon and would be practically relevant for many technologies.

Hollow Micro‐/Nanostructures: Synthesis and Applications

“…[104,105] In a few special cases, core/shell particles made of two materials (or precursors) have been synthesized using one-step approaches based on hydrothermal method or pyrolysis. [106,107] After selectively removing the cores, hollow particles can be obtained. In other words, preparation of templates and formation of shells are combined into one step compared to conventional hard templating.…”

Thin‐Walled Carbon Nanocages: Direct Growth, Characterization, and Applications

“…Catalytic template approaches generate large-sized CNCs (> 20 nm), but with thick walls (> 10 graphitic layers) and thus low surface areas. [5][6][7] Furthermore, the major processing route towards carbon nanomaterials with a graphitic structure (carbon nanotubes, nanofibers, and CNCs) has been the catalytic decomposition of molecules containing carbon atoms. [5][6][7][8] However, the removal of all the catalysts from the deposited carbon materials requires strong acids, which also damage the structures of the nanomaterials.…”

Synthesis and electrochemical applications of nitrogen-doped carbon nanomaterials

“…The nitrogen-doped hollow spherical CSs (carbon nanocage or nanoparticles) have been extensively investigated in the recent years. These are the kind of nanocarbons with a graphitic shell and a hollow interior, show great potential applications in the widespread fields with the advantages of their low density, large surface area, good electrical conductivity, as well as performance stability [188][189][190]. These core/shell nanostructures of the carbon materials are adequately synthesized by several methods [191,192], including the pyrolysis of the carbon nanofibers and the nitrogen-doped graphitic layer pyrolysis as a core and shell, respectively.…”