Surface structure and properties of functionalized nanodiamonds: a first-principles study.

Area of Science:

• Materials Science
• Computational Chemistry
• Nanotechnology

Background:

• Detonation nanodiamonds (NDs) possess unique surface structures enabling functionalization for drug molecule binding.
• Modeling the surface properties and drug-ND interactions during functionalization presents a significant challenge.

Purpose of the Study:

• To achieve a fundamental understanding of the surface and internal structure of functionalized detonation nanodiamonds (NDs).
• To investigate the effects of functionalization on ND stability and surface reactivity using computational methods.

Main Methods:

• Optimization of nanodiamond (ND) structures (∼5 nm) using molecular mechanics simulations.
• Analysis of smaller, relevant ND parts using quantum mechanics-based density functional theory (DFT) calculations.
• Evaluation of functionalization effects on surface stability and reactivity.

Main Results:

• Functionalization is favored over reconstruction on the (100) surface of NDs.
• Carbonyl oxygen (C=O) functionalization promotes graphitization on the (111) surface.
• Carboxyl (-COOH) group functionalization preferentially occurs at the edges rather than the corners of NDs.

Conclusions:

• Computational modeling provides key insights into the behavior of functionalized nanodiamonds.
• Understanding functionalization mechanisms is crucial for designing NDs for drug delivery and other applications.