A facile one-pot and alkali-free synthetic procedure for binary SnO2/g-C3N4 composites with enhanced photocatalytic behavior

Abstract In this investigation, a facile alkali-free one-pot synthetic protocol was developed to construct binary SnO2/g-C3N4 composites for sake of environment friendliness. These composites were systematically characterized by various analytical techniques. X-ray powder diffraction (XRD) patterns, Fourier-transform infrared spectra (FT-IR), and X-ray photoelectron spectra (XPS) identified the coexistence of both components that were closely combined to generate heterojunction structures proven by high resolution transmission electron microscope (HRTEM) observations. These binary composites showed enhanced photocatalytic performance over methyl orange decolorization under visible light irradiation in comparison to bare g-C3N4, mostly attributing to morphological harmony of both ingredients, formation of heterojunction domains, and well-aligned band structures. Besides, the satisfactory reusability and structural stability of composites were identified. Basing on entrapping experiments and electron spin resonance (ESR) analyses, a possible photocatalysis mechanism was preliminarily inspected. It was noted that the variation of real weight percent of SnO2 in composites was constrained to some degree, which should be settled in future work by appropriate modifications of such synthetic protocol.