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An artificial all-solid-state Z-scheme Bi 2 MoO 6 /CNTs/ g -C 3 N 4 composite has been synthesized by hydrothermal technique, and its photocatalytic properties was investigated by the debromination and degradation of 2,4-dibromophenol (2,4-DBP). The morphology and surface analysis indicated that the Bi 2 MoO 6 /CNTs/ g -C 3 N 4 composite was a veritable ternary heterojunction rather than a simply physical mixture. The CNTs acted as excellent electron mediator for charge transfer due to the matched Fermi level between the Bi 2 MoO 6 and g -C 3 N 4 . The unique Z-scheme structure had a remarkable contribution to affect the recombination of the electrons and holes. The optimal Bi 2 MoO 6 /CNTs/ g -C 3 N 4 composite exhibited an outstanding photocatalytic activity than the pure Bi 2 MoO 6 and g -C 3 N 4 for the debromination and degradation of 2,4-DBP. The photoexcited electrons aggregated in the g -C 3 N 4 conduction band, and the holes in the Bi 2 MoO 6 valence band have played equally important roles in the 2,4-DBP degradation. Debromination was the primary step for 2,4-DBP degradation, and the debromination process was launched by the photoexcited electrons aggregated in the g -C 3 N 4 conduction band. The major intermediates during the debromination process were monobrominated and bromine-free products. Finally, the intermediates were mineralized by the photoexcited holes and the subsequent hydroxyl radicals. [ABSTRACT FROM AUTHOR]

An efficient visible-light-driven Z-scheme g -C 3 N 4 /RGO/Bi 2 WO 6 composite was fabricated by the hydrothermal method. The prepared g -C 3 N 4 /RGO/Bi 2 WO 6 composite were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen sorption, Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectrometer (XPS). The photocatalytic activity of the g -C 3 N 4 /RGO/Bi 2 WO 6 composite was evaluated by the degradation of 2,4,6-trichlorophenol (TCP) under visible-light irradiation. The photochemical test and scavenging experiment showed the photogenerated electrons (e − ) and holes (h + ) had strong reducing capability and oxidation capability, respectively. The photocatalytic activity of the g -C 3 N 4 /RGO/Bi 2 WO 6 composite was higher than that of the pure g -C 3 N 4 , Bi 2 WO 6 , and g -C 3 N 4 /Bi 2 WO 6 during the TCP degradation, which could be due to the efficient visible-light utilization efficiency and the construction of Z-scheme. RGO served as a charge transmission bridge between the g -C 3 N 4 and the Bi 2 WO 6 , and the Z-scheme kept the electrons with high reducing capability in the conduction band (CB) of g -C 3 N 4 and the holes with high oxidation capability in the valence band (VB) of Bi 2 WO 6 . The photogenerated holes of Bi 2 WO 6 were the major active species in the TCP oxidative degradation, and the photogenerated electrons of g -C 3 N 4 were the major active species in the TCP dechlorination. [ABSTRACT FROM AUTHOR]