Oxidative transformation of Ti₃C₂Tₓ MXene on gamma radiation exposure in aqueous media

MXenes are promising for applications from energy storage to environmental remediation, yet their stability under ionizing radiation is largely unexplored. This study elucidates the fundamental mechanisms governing the radiation-induced transformation of Ti₃C₂Tₓ MXene through comprehensive spectroscopic, structural, and functional analysis. We demonstrate that radiation initiates a systematic oxidative transformation of the metallic MXene into semiconducting TiO₂ nanostructures. This process, driven by surface oxidation and Ti-C bond cleavage, is confirmed by the disappearance of MXene’s characteristic plasmonic absorbance at 790 nm and the emergence of TiO₂ features. The degradation kinetics exhibit remarkable atmospheric dependency, accelerating significantly in oxygen-rich environment due to radiation-generated reactive oxygen species. This transformation severely deteriorate MXene’s functional properties, causing a loss of electrical conductivity and a dramatic drop in methylene blue adsorption capacity from 87 to 31% at a 250 kGy dose. These findings establish a mechanistic framework for predicting MXene stability in radiation-intensive environments, providing essential guidelines for their implementation in radiation-intensive applications spanning environmental remediation, energy conversion, and space technologies.