Near-Infrared Photothermal Conversion Agent Oxygen-Deficient Molybdenum Dioxide: Preparation and Application in Photothermal Therapy

In this paper, molybdenum dioxide (MoO2) nanoparticles were prepared by hydrothermal synthesis method using molybdenum pentachloride (MoCl5) as molybdenum source and polyvinylpyrrolidone (PVP) as a structural guiding agent as well as reducing agent. The results from X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV-Vis-near-infrared (UV-Vis-NIR) absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron spin resonance spectroscopy (EPR) illustrated that the diameter of the prepared MoO2 nanoparticles were about 18 nm. The particle size was uniform with abundant oxygen defects, and had good light absorption ability in the near-infrared region of 650-1 100 nm. The photothermal test demonstrated that the 100 mu g center dot mL(-1) aqueous solution of the material heated up 31.5. within 10 min, the photothermal conversion rate was up to 67.9% with excellent photothermal stability. Cytotoxicity test showed that the nanomaterial had no toxicity to cells, meanwhile possessing an obvious photothermal killing effect on hepatoma cells.