Template-free synthesis of graphitic carbon nitride hollow spheres for photocatalytic degradation of organic pollutants

Abstract Graphitic carbon nitride (g-C 3 N 4 ) hollow spheres have been prepared via one-step solvothermal method without templates. The effects of condensation temperature on the structural, optical and photocatalytic properties of the samples were investigated. The X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) results show that the samples synthesized at dissimilar temperatures have graphitic and heptazine-based conjugate structure. Optical analysis results evidence that the absorption edge shifts toward longer wavelength and PL intensity quenches quickly as the treating temperature increases from 120 °C to 180 °C. The results demonstrate that higher condensation temperature improves the visible-light absorption and migration rate of photo-induced carriers of samples. The g-C 3 N 4 sample prepared at 180 °C presents a highest photocatalytic degradation activity in the degradation of RhB under visible-light irradiation. This study demonstrates a novel strategy for one-step synthesis of hollow spheres shaped polymer semiconductor photocatalyst without templates.