Antioxidant‐Driven Stabilization of MXenes: Density Functional Theory Insights Into Long‐Term Oxidative Protection

MXenes are a family of two‐dimensional transition metal carbides, nitrides, and carbonitrides derived from layered MAX phases. an emerging family of two‐dimensional (2D) material, yet remain critically limited by their susceptibility to oxidative degradation under ambient conditions. Herein, we report a bioinspired molecular passivation strategy wherein Ti 3 C 2 T x nanosheets are functionalized with catechin, a naturally occurring antioxidant, to markedly enhance their oxidative stability. Catechin anchors to the MXene surface through a combination of hydrogen bonding, π–π interactions, and coordination with titanium centers, forming a conformal molecular sheath that imparts significant protection against oxidation. X‐ray photoelectron spectroscopy reveals a pronounced suppression of Ti 4+ –TiO 2 formation and concurrent enrichment of surface‐bound oxygenated carbon species, consistent with effective chemical passivation. Ultraviolet photoelectron spectroscopy and Tauc analysis demonstrate that catechin functionalization lowers the work function by 0.4 eV, shifts the valence band maximum downward by 1.5 eV, and drives a transition in the optical bandgap from indirect (1.1 eV) to direct (2.6 eV). Transmission electron microscopy confirms structural integrity with an interlayer spacing of 1.18 nm, while elemental mapping indicates uniform catechin distribution across the nanosheet surface. First‐principles density functional theory calculations further reveal strong catechin adsorption ( E ad = –1.0 eV) and weakened interactions with oxidative species such as O 2 (–0.14 eV) and H 2 O (–0.2 eV), highlighting the molecular shielding effect. These findings establish catechin‐functionalized MXenes as chemically durable and electronically tunable nanomaterials and offer a sustainable, generalizable approach for stabilizing oxidation‐prone 2D systems.