Doping graphitic and carbon nanotube structures with boron and nitrogen

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Carbon nanotubes (CNTs) are widely studied for their unique properties.
• Boron nitride (BN) materials offer distinct electronic and thermal characteristics.
• Combining carbon and boron nitride could lead to novel composite materials with enhanced functionalities.

Purpose of the Study:

• To synthesize and characterize composite materials containing carbon, boron, and nitrogen.
• To investigate the structural and compositional relationships between these elements in nanotubes and sheets.
• To explore the potential formation of novel ternary compounds like carbon boron nitride (CyBxNx).

Main Methods:

• Electric arc discharge synthesis using graphite cathodes and boron-filled graphite anodes in a nitrogen atmosphere.
• Characterization using electron energy-loss spectroscopy (EELS) to determine elemental concentration profiles and fine structures.
• Analysis of core energy-loss fine structures to understand bonding and structural arrangements.

Main Results:

• Successful synthesis of composite sheets and nanotubes containing carbon, boron, and nitrogen.
• Observed a one-to-one correlation between boron and nitrogen concentrations.
• Detected anticorrelation between boron and carbon, suggesting boron and nitrogen substitution into the carbon lattice.
• Identified structural differences compared to pure hexagonal boron nitride.

Conclusions:

• The synthesis method is effective for creating carbon-boron-nitrogen composites.
• Boron and nitrogen likely substitute into the carbon network, forming novel CyBxNx phases or domains.
• The findings suggest the potential existence of single-phase CyBxNx materials or nanoscale boron nitride domains within carbon networks.