Construction of Cu2O ternary composite comprising SiC and g-C3N4 for improved photocatalytic degradation of methyl orange via synergetic Z-scheme effect

Cu 2 O–SiC/g-C 3 N 4 composite photocatalysts with excellent photocatalytic performance under visible light were synthesized for the first time via a facile approach combining calcination with hydrothermal reaction. Comprehensive characterization of the synthesized samples encompassing composition, morphology, structure and photoelectric properties was conducted utilizing techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and electrochemical impedance spectroscopy (EIS). Results unequivocally demonstrate successful preparation of the ternary composite through Cu 2 O loading onto SiC/g-C 3 N 4 , evincing markedly elevated activity compared to individual counterparts and binary composites. Notably, in the presence of the prepared Cu 2 O–SiC/g-C 3 N 4 , the degradation rate of methyl orange reached 93.70 % under illumination with a visible LED light rated at 5 W. The notable enhancement in photocatalytic performance of the ternary composites is primarily ascribed to the synergistic effects stemming from the formation of p-n junctions between Cu 2 O and g-C 3 N 4 , alongside the Z-scheme configuration established between Cu 2 O and SiC. Free radical quenching experiments corroborated •O 2 − and h + as the principal redox species mediating the visible light quenching process. This study not only presents a feasible strategy for the fabrication of Cu 2 O-based ternary composites with significantly augmented photocatalytic performance but also delineates a novel avenue for the design and construction of composite photocatalysts facilitating enhanced charge-carrier generation and separation concomitantly.