A DFT study on the central-ring doped HBC nanographenes

Area of Science:

• Materials Science
• Computational Chemistry
• Condensed Matter Physics

Background:

• Nanographenes (NGs) are hydrogen-terminated graphene fragments with unique properties.
• Doping NGs with elements like Boron (B), Aluminum (Al), Nitrogen (N), and Phosphorus (P) can tune their characteristics.
• Understanding these modifications is key for novel material applications.

Purpose of the Study:

• To investigate the electronic, thermodynamic, optical, and structural properties of C36X3Y3H18 nanographenes.
• To evaluate the stability and conductivity of doped nanographenes.
• To explore their exciton behavior and solubility.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Properties analyzed include molecular structure, inversion energy, enthalpy of formation, electrical conductivity, exciton binding energy, and Gibbs free energy of solvation.

Main Results:

• BN-NG is planar; others are buckybowl-shaped with high inversion barriers.
• Energetic stability follows BN > AlN > BP > AlP; BN and AlN are stable at room temperature.
• Electrical conductivity is inversely proportional to stability.
• Exciton binding energy is 0.57–0.75 eV (Frenkel type).
• NGs are insoluble in organic solvents but partially soluble in water.

Conclusions:

• BN and AlN doped nanographenes exhibit promising stability and conductivity for potential applications.
• The structural and electronic properties are significantly influenced by dopant type.
• Solubility in water suggests possibilities for solution-based processing.