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 Ag 2 O/Bi 2 MoO 6 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 activity 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 Ag 2 O/Bi 2 MoO 6 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 Bi 2 MoO 6 (32%). And 1:5 Ag 2 O/Bi 2 MoO 6 exhibited the highest photocurrent efficiency (0.8 μA/cm 2 ). Meanwhile, the efficiency of 1:5Ag 2 O/Bi 2 MoO 6 keep 90% after four cycles. The enhanced activity can be attributed to the formation of a good interfacial contact between Ag 2 O and Bi 2 MoO 6 . 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 perspective for the rational design of excellent Bi 2 MoO 6 -based Z-scheme heterojunctions for environmental remediation.