Excellent photocatalytic activity of MoO3-adorned g-C3N4 systems: Construction of S-scheme heterojunction

To alleviate harmful pollutants in water, photocatalytic technology, which offers green degradation of pollutants, is being used. The g-C3N4 is a metal-free organic polymer semiconductor photocatalyst widely used in photocatalysis. However, some drawbacks have limited its practical application. Thus, constructing of semiconductor heterojunction with appropriate band structure to improve photocatalysis activity for g-C3N4 is an effective and common means to overcome the drawbacks. Therefore, in this study, MoO3/g-C3N4 (MoCN) was prepared via the one-step calcination method. The photocatalytic performance of the composite was evaluated via photocatalytic degradation of rhodamine B (RhB) and the data revealed that the 3MoCN composite semiconductor greatly enhanced the activity (about 6.3 times) of pure g-C3N4 toward the degradation of RhB. Meanwhile, the free radical masking experiments suggested center dot O-2(-) as the major oxidizing species in the MoCN system. The specific area of the composite system of MoCN was 3.7-fold higher than that of pure g-C3N4. Furthermore, the photoelectric properties tests and DFT demonstrated improved photoactivity of MoO3/g-C3N4 due to the movement of Fermi levels and built-in electric field close to the S-scheme heterojunction interface. Our work demonstrated a simple strategy to prepare efficient photocatalysts for environmental remediation.

Automated summary

This study focuses on improving the photocatalytic activity of g-C3N4 by constructing a semiconductor heterojunction. The MoO3/g-C3N4 composite was prepared and showed significantly enhanced photocatalytic degradation of rhodamine B compared to pure g-C3N4. The experiments suggested the major oxidizing species in the MoCN system and the composite had a larger specific area than pure g-C3N4. Additionally, the photoelectric properties tests and DFT analysis demonstrated the improved photoactivity of the MoO3/g-C3N4 composite.