Noble metal-decorated MXene for broadband and high-efficiency photothermal conversion.

Two-dimensional MXenes, owing to their metallic conductivity and unique optical properties, hold immense potential for advanced technologies spanning energy conversion, biomedical therapy, and intelligent thermal management. However, achieving precise and synergistic control over their optical performance across the entire solar and infrared spectrum remains a significant challenge, limiting their effectiveness in multi-functional devices. Here, we demonstrate a facile in-situ reduction strategy for fabricating noble metal nanoparticle-decorated MXene composites. We show that the resulting materials exhibit a remarkable combination of properties, including a weighted solar absorptance of up to 92.69%, potent near-infrared photothermal sterilization with a bacterial survival rate as low as 0.04%, and dynamically tunable mid-infrared emissivity. Unlike traditional modification strategies that often enhance one property at the expense of another, our approach creates a synergistic performance combination. The plasmonic heterointerface concurrently enhances photothermal conversion and enables effective thermal radiation management. This strategic balance between performance metrics provides a versatile platform for designing adaptive materials. These findings establish a strategy for developing multi-spectral smart materials with integrated capabilities for energy harvesting, biomedical therapy, and advanced thermal regulation.