Deep Eutectic Solvent Functionalized Graphene Composite as an Extremely High Potency Flame Retardant.

We report a simple and green approach to develop the deep eutectic solvent functionalized graphene derivative as an effective flame retardant. The deep eutectic solvent functionalized graphene oxide (DESGO) was synthesized by introducing nitrogen-supported phosphorus functional groups on the surface of graphene derivative via a deep eutectic solvent, which is prepared by the treatment of monosodium dihydrogen orthophosphate and choline chloride. Subsequently, the resultant DESGO material is characterized by X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The as prepared DESGO solution coated cloth piece was sustaining its initial shape and size by releasing a little amount of smoke at the early stage without catching fire for more than 540 s (9 min), whereas the pristine cloth is totally burned out within 10 s, leaving small amounts of black mass. This simple method of directly functionalized deep eutectic solvent on a graphene oxide surface can be a common process for the cost-effective bulk production of a nano carbon template for extremely high potency, nontoxic flame retardant applications.