In-situ One-Pot Novel Synthesis of Molybdenum di-Telluride@Carbon Nano-Dots for Sensitive and Selective Detection of Hydrogen Peroxide Molecules via Turn-off Fluorescence Mechanism

Transition metal dichalcogenides (TMDs) based materials have grabbed striking attention to a great extent owing to their intriguing characteristics for biological, optical, chemical and medicinal applications. Herein, we report in-situ one-pot hydrothermal-synthesis of molybdenum ditelluride@carbon nano-dots (MoTe2@C NDs) and then explored its potency in biosensing. The MoTe2@C NDs have been characterized by using X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy and Transmission Electron Microscopy (TEM) for confirmation. Furthermore, the photophysical properties of MoTe2@C NDs have been examined. Under radiation of Ultra-Violet (UV) light (lambda = 365 nm), the MoTe2@C NDs emit cyan fluorescence which has been confirmed by photoluminescence (PL) spectroscopy (PL peak at similar to 431 nm, excitation wavelength similar to 350 nm). The as-synthesized sample has been subjugated for the sensing of hydrogen-peroxide (H2O2) molecules. Notably, with a gradual proliferation of the concentration of H2O2, the PL intensity of the MoTe2@C NDs decreases and is found to be linear (R-2 = 0.9986). The detection-limit has also been estimated as 14.22 nM. The PL quenching-mechanism has been elucidated based on three-level kinetic model considering charge separated-trap states ((1)[D+center dot center dot center dot A(-)] <-> (3)[D+center dot center dot center dot A(-)]). This is the first work of hydrothermal-synthesis of MoTe2@C NDs and study of its optical properties, which has efficient potential to use as H2O2 sensor in industrial/biomedical applications.