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In Situ Hydrothermal Construction of Direct Solid-State Nano-Z-Scheme BiVO₄/Pyridine-Doped g-C₃N₄ Photocatalyst with Efficient Visible-Light-Induced Photocatalytic Degradation of Phenol and Dyes.

ABSTRACT: In the current study, a mediator-free solid-state BiVO₄/pyridine-doped g-C₃N₄ nano-Z-scheme photocatalytic system (BDCN) with superior visible-light absorption and optimized photocatalytic activity was constructed via an in situ hydrothermal method for the first time. The pyridine-doped g-C₃N₄ (DCN) nanosheets show strong absorbance in the visible-light region by pyridine doping, and the BiVO₄ (∼10 nm) nanoparticles are successfully in situ grown on the surface of DCN nanosheets by the controlled hydrothermal method. Under the irradiation of visible light (λ > 420 nm), the BiVO₄/DCN nanocomposite photocatalysts efficiently degrade phenol and methyl orange (MO) and display much higher photocatalytic activity than the individual DCN, bulk BiVO₄, or the simple physical mixture of DCN and BiVO₄. The greatly improved photocatalytic ability is attributed to the construction of the direct Z-scheme system in the BiVO₄/DCN nanocomposite free from any mediator, which leads to enhanced separation of photogenerated electron-hole pairs, as confirmed by the photocurrent analysis. The possible Z-scheme mechanism of the BiVO₄/DCN nanocomposite photocatalyst was investigated by transient time-resolved luminescence decay spectrum, active species trapping experiments, electron paramagnetic resonance (EPR) technology, and hydrogen evolution test.

SUBMITTER: Meng Q

PROVIDER: S-EPMC6640956 | biostudies-literature |

REPOSITORIES: biostudies-literature

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