Mechanistic elucidation of vacancy-induced polarization transfer in graphite
Year: 2026
Type: article
Abstract: A comprehensive understanding of vacancy-induced strengthening and polarization mechanisms is essential for enhancing the mechanical and electrical performance of nuclear graphite, wherein the vacancy-governed bond contraction and polarization-transfer mechanism may provide a possible theoretical framework for elucidating irradiation-induced defect formation and property modulation. This study investigated the intrinsic nature of vacancy-induced dipole superposition, polarization transfer, and their coupled electromechanical effects in an undercoordinated graphite system. It identified a dual mechanism involving bond contraction and dipole polarization in this system. Results show that a single vacancy enhances the mechanical strength of graphite within the microstrain regime (<0.8%), with C–C bonds between undercoordinated carbon atoms contracting by ∼2.4%. Charge redistribution generates ring-like distributions of energy and electron density around vacancies. Fermi peak emerge at the Fermi level, with the α- and β-vacancy polarization transfer quantified: polarization peak intensities reach ∼0.45% higher at α1 than at α 3 . Hydrogen adsorption at β vacancies is strongly exothermic, with calculated adsorption energies of −3.64 eV and H–C bond lengths of ∼1.513 Å. These findings provide a quantitative basis for understanding irradiation-induced defect formation and property modulation in nuclear graphite.
Authors: Jun Hui, Xue Bang Wu
Institutions: Chinese Academy of Sciences, Institute of Solid State Physics
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,730
Awards: G306282750, G3252910691, G8094761699
OpenAlex ID: W7149595431