Self-Limiting Sub-5 nm Nanodiamonds by Geochemistry-Inspired Synthesis.
Small
; 19(33): e2300659, 2023 Aug.
Article
em En
| MEDLINE
| ID: mdl-37072896
ABSTRACT
Controlling diamond structures with nanometer precision is fundamentally challenging owing to their extreme and far-from-equilibrium synthetic conditions. State-of-the-art techniques, including detonation, chemical vapor deposition, mechanical grinding, and high-pressure-high-temperature synthesis, yield nanodiamond particles with a broad distribution of sizes. Despite many efforts, the direct synthesis of nanodiamonds with precisely controlled diameters remains elusive. Here the geochemistry-inspired synthesis of sub-5 nm nanodiamonds with sub-nanometer size deviation is described. High-pressure-high-temperature treatment of uniform iron carbide nanoparticles embedded in iron oxide matrices yields nanodiamonds with tunable diameters down to 2.13 and 0.22 nm standard deviation. A self-limiting, redox-driven, and diffusion-controlled solid-state reaction mechanism is proposed and supported by in situ X-ray diffraction, ex situ characterizations, and computational modeling. This work provides a unique mechanism for the precise control of nanostructured diamonds under extreme conditions and paves the road for the full realization of their potential in emerging technologies.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article