Materials Chemistry and Physics, Vol.214, 28-33, 2018
In situ synthesis of carbon/g-C3N4 composites for visible light catalysis by facile one-step pyrolysis of partially formaldehyde-modified dicyandiamide
Herein, novel carbon/g-C3N4 composites (C/CN) with improved photocatalytic activity were obtained via a facile one-pot pyrolysis and cost effective method using partially formaldehyde-modified dicyandiamide as a precursor. The structures of carbonig-C3N4 composites were characterized by infrared spectra (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV Vis diffuse reflectance spectroscopy (UV vis DRS), photoluminescence (PL) emission spectra, and electrochemical impedance spectroscopy (EIS). The newly prepared composites showed much higher surface area and better performance for the photocatalytic degradation of methylene blue (MB) than that of pristine g-C3N4 (CN) under visible light irradiation. The enhancement of photocatalytic activity might be ascribed to the introduction of residual carbon derived from incompletely in situ pyrolysis of formaldehyde-modified dicyandiamide, which was beneficial to the appropriate adjustment of CN band gap and the efficient transfer and separation of photo-excited carriers. The possible photo-catalyitc degradation mechanism of the as-prepared composites under visible light irradiation for MB was also elucidated. (C) 2018 Elsevier B.V. All rights reserved.