Fabrication of direct Z-scheme Ag2O/Bi2MoO6 heterostructured microsphere with enhanced visible-light photocatalytic activity

Rational design of Z-scheme heterojunction is known to be a good strategy for promoting photogenerated charge efficient separation. In this paper, a direct Z-scheme Ag2O/Bi2MoO6 heterostructured microspheres with good interfacial properties were successfully prepared by hydrothermal synthesis-coprecipitation-calcination decomposition. Various techniques such as Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and powder X-ray diffraction (PXRD) were used to reveal the structure, morphology, composition, electrochemical and optical properties of the target product. The catalytic ac-tivity of the as-prepared composite was evaluated by visible light degradation of Rhodamine B (RhB) and transient photocurrent. As expected, the results showed that 1:5 Ag2O/Bi2MoO6 exhibited the optimal catalytic performance. And the visible degradation efficiency is up to 86% in 90 min, which was 2.69 times higher than that of Bi2MoO6 (32%). And 1:5 Ag2O/Bi2MoO6 exhibited the highest photocurrent efficiency (0.8 mu A/cm2). Meanwhile, the efficiency of 1:5Ag2O/Bi2MoO6 keep 90% after four cycles. The enhanced activity can be attributed to the formation of a good interfacial contact between Ag2O and Bi2MoO6. In addition, hole and superoxide were identified as the main active species. Eventually a possible direct Z -scheme mechanism was proposed to explain enhanced performance. This work may provide a new per-spective for the rational design of excellent Bi2MoO6-based Z-scheme heterojunctions for environmental remediation.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this paper, a direct Z-scheme Ag2O/Bi2MoO6 heterostructured microspheres with good interfacial properties were successfully prepared. Various techniques were used to characterize the structure, morphology, composition, electrochemical and optical properties of the product. The composite exhibited excellent catalytic performance, with a visible degradation efficiency of 86% in 90 minutes and a photocurrent efficiency of 0.8 mu A/cm2. The enhanced activity was attributed to the formation of a good interfacial contact between Ag2O and Bi2MoO6, and hole and superoxide were identified as the main active species. This work provides a new perspective for the rational design of Bi2MoO6-based Z-scheme heterojunctions for environmental remediation.