Ultrathin Molybdenum Carbide MXene with Fast Biodegradability for Highly Efficient Theory-Oriented Photonic Tumor Hyperthermia

The explosion of emerging high-performance 2D MXenes in theranostic nanomedicine is still at the preliminary stage. Despite tremendous efforts devoted to photonic tumor hyperthermia, current photothermal-conversion nanoagents still suffer from critical issues preventing further clinical translation such as low biodegradability. Here, for the first time, the construction of novel 2D molybdenum carbide (Mo2C) MXenes for photonic tumor hyperthermia is reported. The structure of both bulk Mo2Ga2C ceramic and Mo2C MXene is fully revealed. Especially, computational simulation, as a novel strategy and a powerful tool for photonic-performance prediction, is employed to reveal that Mo2C MXene is featured with intense near-infrared (NIR) absorption, covering the first and the second biological transparency window (NIR I and II). After further surface engineering with polyvinyl alcohol (PVA), Mo2C-PVA nanoflakes exhibit high biocompatibility and fast degradability. Importantly, it is experimentally corroborated that Mo2C-PVA nanoflakes possess intriguing broad absorption band spanning NIR in both the I and II regions, and desirable photothermal-conversion efficiency (24.5% for NIR I and 43.3% for NIR II). This study not only broadens the nanomedical applications of MXene by fabricating novel material members (Mo2C), but also provides the paradigm of inorganic multifunctional biomedical nanoplatform with desirable biodegradability and high therapeutic performance.