Flower-Like Ag6Si2O7/Bi12O17Cl2 p-n Heterojunctions: Enhanced Photocatalytic Activity and Mechanistic Insight

Photocatalytic degradation is one of the effective ways to remove dyes. Accelerating the separation of photogenerated charge is an effective method for high efficiency visible-driven catalysis. Here, a potential flower-like Ag6Si2O7/Bi12O17Cl2 p-n heterojunctions were successfully prepared. Ag6Si2O7/Bi12O17Cl2 can achieve light capture in a wider range of visible light and provide directional channel for carrier to achieve more efficient space charge separation. The constructed Ag6Si2O7/Bi12O17Cl2 showed excellent photocatalytic removal of 25 mg/L (100 mL) Rhodamine B (RhB) within 20 min. The rate constant for RhB degradation was 0.202 min(-1) by Ag6Si2O7/Bi12O17Cl2-2 which was more than 3.6 times greater than Bi12O17Cl2 (0.055 min(-1)) and 3.2 times greater than Ag6Si2O7 (0.063 min(-1)). In addition, the results of free radical capture experiment indicate the *OH plays a leading role in the photocatalytic degradation of RhB and a possible Z-scheme charge transfer paths and the formation of active species over Ag6Si2O7/Bi12O17Cl2 was proposed to elucidate the reaction mechanism.

Automated summary

A flower-like Ag6Si2O7/Bi12O17Cl2 p-n heterojunctions with potential was successfully prepared, which can capture light in a wider range of visible light and provide a directional channel for carrier to achieve more efficient space charge separation. The constructed Ag6Si2O7/Bi12O17Cl2 showed excellent photocatalytic removal of Rhodamine B within a short time, with a higher rate constant compared to Bi12O17Cl2 and Ag6Si2O7. Furthermore, the *OH radicals were found to play a leading role in the photocatalytic degradation, and a possible Z-scheme charge transfer paths and the formation of active species over Ag6Si2O7/Bi12O17Cl2 were proposed to elucidate the reaction mechanism.