Simple systematic synthesis of size-tunable covalent organophosphonitridic framework nano- and microspheres

Abstract

Covalent organophosphonitridic framework nano- and microspheres were synthesized by a condensation reaction between hexachlorocyclotriphosphazene (PNC) and 3,3′-diaminobenzidine (DAB) in anhydrous dimethylformamide (DMF) at a temperature of 125 °C in the presence of polyvinyl pyrrolidone (PVP). The spheres were almost monodisperse and the diameter could be adjusted from 80 nm to 1.5 μm by varying the concentration of the reactants PNC and DAB. The spheres are thermally stable up to 480 °C in air and are completely oxidatively-depolymerized at 750 °C.