Holey MXenes have recently emerged as a promising extension of the MXene family, in which in‐plane porosity enhances ion transport, exposes defect‐rich edges, and can create confined domains useful for modulating reactivity. In this work, we present a systematic density functional theory and ab initio molecular dynamics (AIMD) investigation of the structural and electronic properties of holey Ti 3 C 2 O 2 and Ti 2 CO 2 MXenes. Edge stability was assessed through nanoribbon models, revealing that OTiC–TiCO edges reconstruct into Ti 3 O tetrahedra and represent the most stable configuration. Hole formation energies were evaluated for pores of increasing size up to approximately 2.1 nm, showing enhanced stability with increasing pore size, and oxygen‐rich walls stabilise the pores. TiO bond lengths and charges are nearly identical at edges and pore walls, highlighting their chemical similarity. Electronic band structures indicate that metallic behaviour is preserved for all edge and hole models, independent of porosity, consistent with experimental observations for titanium carbide MXenes. AIMD simulations at 300 K further demonstrate the thermal stability of holey MXenes and highlight the tendency of undercoordinated sites to attract terminations. Our results provide atomistic insights into the stability and electronic resilience of holey MXenes, advancing their rational design for applications in catalysis, sensing, and energy storage.
Gouveia et al. (Fri,) studied this question.