Chang Song

Synthesis of highly nitrogen-doped hollow carbon nanoparticles and their excellent electrocatalytic properties in dye-sensitized solar cells

Hollow carbon nanoparticles that have been highly doped with nitrogen (N-HCNPs) are directly prepared by a facile one-pot method based on the detonation-assisted chemical vapor deposition of dimethylformamide without the use of metal catalysts. The N-HCNPs exhibit uniform core-shell microstructures with inner cavities encapsulated by graphitic walls, possessing a narrow size distribution of 10–25 nm. The nitrogen content in N-HCNPs is as high as 20.8% atom ratio, and the nitrogen bonds display pyridine-, pyrrole-, and graphite-like configurations. Defects and dislocations are present in the graphene layers due to highly incorporated nitrogen, leading to the creation of micropores on the carbon shell and a large BET surface area of 454 m2 g−1. The unique N-HCNPs with interconnected hierarchical porous structures and nitrogen-containing defects show excellent electrocatalytic activity for triiodide reduction in dye-sensitized solar cells, superior to conventional platinum catalysts.

Cyclohexane dehydrogenation over the platinum catalysts supported on carbon nanomaterials

Abstract Platinum catalysts supported on carbon nanoparticles and other carbon materials were prepared. Their surface area, structure, morphology, and particle size were characterized by nitrogen sorption, transmission electron microscopy, and X-ray diffraction. The activity of various catalysts for cyclohexane dehydrogenation was investigated under different reaction temperatures. The results showed that Pt particles were well dispersed on the surface of nanoparticles, and the size distribution was in a narrow range; the Pt catalyst supported on the hollow carbon nanoparticles exhibited excellent activity and stability compared to the other carbon materials supported Pt catalysts.

Identification and technical accessibility of the carbon self-assembly concept hidden in catalytic carbon nanotube evolution

Multi-wall carbon nanotubes can readily form by the catalysis of lanthanide oxides. The formed tubes are unusually separated from the catalyst particles, which leads to a straightforward identification of the self-assembly of carbon particles that is hidden in the chaotic carbon-catalyst-hybrid system of catalytic carbon nanotube evolution. Following the identified self-assembly concept, conventional bulk activated carbon (AC) has been successfully transformed into CNTs through a detonation-induced cracking of AC and a real-time re-organization.

Theoretical and experimental evidence of a metal-carbon synergism for the catalytic growth of carbon nanotubes by chemical vapor deposition

The nucleation and growth of carbon nanotubes (CNTs) using chemical vapor deposition with a metal-carbon catalyst have been studied experimentally and theoretically. Results suggest that the nucleation and growth of multiwalled CNTs are not due to the metal alone, but that carbon nuclei (once formed) also contribute to radial and axial growth. Metal particles mainly promote the nucleation and growth of the innermost carbon shell (s), and catalyze the ordering of the carbon atoms to form graphene structures. The intrinsic difference between multiwalled CNT formation and single-walled CNT formation seems to be associated with a self-catalytic function of carbon nuclei.