Designing Ag2O modified g-C3N4/TiO2 ternary nanocomposites for photocatalytic organic pollutants degradation performance under visible light: Synergistic mechanism insight

In this work, an Ag2O modified g-C3N4/TiO2 ternary heterogeneous photocatalyst was prepared through simple calcination and efficient hydrothermal synthesis way. The as-prepared composites were analyzed by powder XRD, FT-IR, HRSEM with EDX mapping, HRTEM, XPS, UV-Vis DRS and PL spectra respectively. The Ag2O modified g-C3N4/TiO2 photocatalyst displays a narrower bandgap and improved the RhB dye photo-degradation efficiency was reached at similar to 94.5% for 60 min under visible light exposure. Also, the reaction rate constant (k) of RhB dye and phenolic impurities degradation efficiencies for g-C3N4/TiO2-Ag2O PCs was 5.8 and 4.97 folds higher than that of pristine g-C3N4. Besides, the g-C3N4/TiO2-Ag2O composite PCs sustained superior photo-degradation performance after the five reusability tests, indicating excellent stability and durability. The excellent photocatalytic performance has been attributed to the synergistic heterostructured formation between Ag/Ag2O among g-C3N4/TiO2 composites, which facilitates the interfacial electron separation/transfer, and great visible-light utilization ability. For experimental results, a possible photo-degradation mechanism was also proposed.

Automated summary

An Ag2O modified g-C3N4/TiO2 ternary catalyst with a narrow bandgap and enhanced photocatalytic performance was successfully prepared in this study. The catalyst showed excellent stability and reusability under visible light exposure. The superior photocatalytic performance was attributed to the synergistic heterostructured formation and effective interfacial electron separation/transfer among the composites.