Heterojuncted non-metal binary composites silicon carbide/g-C3N4 with enhanced photocatalytic performance

Novel visible-light-driven silicon carbide (SiC)/g-C3N4 heterojuncted composites were successfully prepared via a facile ultrasonic dispersion and calcination method, and afterwards characterized by a couple of technologies including XRD, SEM, TEM, FT-IR, XPS, UV-vis DRS, PL spectra, and N-2 adsorption-desorption. It was found that SiC nanoparticles were uniformly deposited over the surface of g-C3N4 to create heterojunction domains along phase interface boundary, favoring charge carriers transfer and separation across the straddling band alignments. Besides, the visible-light absorption capability of samples was enhanced by the incorporation of SiC. These physiochemical merits ensured the improved photocatalytic performance of heterojuncted composites over the degradation of dyes rhodamine B (RhB) and methyl orange (MO) in comparison to each single component SiC or g-C3N4. Upon an identical condition, the sample SN8 exhibited the highest photocatalytic ability among all tested samples. According to active species trapping measurements, center dot OH and center dot O-2(-) were deemed as major radicals and eventually a possible photocatalysis mechanism was speculated.