Synthesis and optical properties of luminescent carbon dots from Haloxylon seeds

In this work, local Haloxylon seeds were utilized as a carbon source to synthesize carbon dots (CDs) using the Pyrolysis method. The morphology, structure, and optical properties of CDs were extensively analyzed. The obtained CDs exhibit a spherical shape with an average diameter of 7.7 nm. They are mainly composed of carbon and oxygen, which formed various hydrophilic functional groups on the surface resulting in enhancement of their water solubility. The CDs emit a bright blue fluorescence under excitation wavelength at 320 nm, with an emission peak at 425 nm and a quantum yield of 1.6 %. The emission characteristics of the CDs is a result of the radiative recombination of the carbon-core state and surface defects, which is dependent on the excitation. This research offers an efficient and environmentally-friendly method for synthesizing luminescent CDs from renewable sources.