Low-temperature one-step synthesis of covalently chelated ZnO/dopamine hybrid nanoparticles and their optical properties

Dopamine covalently chelated ZnO nanoparticles were synthesized by a nonaqueous one-step chemical process at a temperature as low as 60 °C. The formation of ZnO/dopamine hybrid structure was proved by x-ray powder diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) techniques. Detailed absorption, luminescence, and time-resolved decay studies were performed for these ZnO/dopamine hybrid nanoparticles. We observed an enhanced green emission, which could be assigned to a new band-gap emission based on the fast of nanosecond lifetime of the green emission. Our results demonstrated that the change of optical properties of ZnO nanoparticles after covalently chelated b dopamine ligands is closely associated with the formation of new band structure.