Dataset Information

Direct Z-scheme α-MnO₂@MnIn₂S₄ hierarchical photocatalysts with atomically defined junctions for improved photocatalytic activities.

ABSTRACT: The use of semiconductor photocatalysts to generate electrons with efficient reducing capability for organic photoreduction synthesis and the removal of harmful substances has become a hotspot in the field of green chemistry research. In this work, α-MnO₂ nanocubes and α-MnO₂@MnIn₂S₄ hybrid photocatalysts with a core-shell structure were synthesized successively by a two-step method. XRD and XPS verified the coexistence of the two substances (α-MnO₂ and MnIn₂S₄) in hybrid systems. According to the SEM and TEM characterization, it is clearly seen that MnIn₂S₄ nanosheets grow on α-MnO₂ nanocubes to form a hierarchical structure. Furthermore, HRTEM showed that the interface contact between α-MnO₂ and MnIn₂S₄ resulted in an atomically defined junction. The photocatalytic performance of the composite catalyst was evaluated by reducing 4-nitroaniline to 4-phenylenediamine and Cr(vi) to Cr(iii), respectively. The results show that the catalytic activity of the composite material is effectively improved compared to that of the single components. The Z-scheme electron transport mechanism was proved by ultraviolet-visible diffuse reflectance spectroscopy, valence band XPS, energy band structure calculation and active species detection experiments. The constructed Z-scheme hierarchical α-MnO₂@MnIn₂S₄ system with an atomically defined junction can improve the redox performance of semiconductors for organic synthesis and environmental remediation.

SUBMITTER: Zhang M

PROVIDER: S-EPMC9417498 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Direct Z-scheme α-MnO2@MnIn2S4 hierarchical photocatalysts with atomically defined junctions for improved photocatalytic activities.

Zhang Min M Arif Muhammad M Hua Yuxiang Y Qiu Bo B Mao Yue Y Liu Xiaoheng X

Nanoscale advances 20201211 3

The use of semiconductor photocatalysts to generate electrons with efficient reducing capability for organic photoreduction synthesis and the removal of harmful substances has become a hotspot in the field of green chemistry research. In this work, α-MnO2 nanocubes and α-MnO2@MnIn2S4 hybrid photocatalysts with a core-shell structure were synthesized successively by a two-step method. XRD and XPS verified the coexistence of the two substances (α-MnO<sub ...[more]

PMID: 36133852

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Dataset Information

Direct Z-scheme α-MnO₂@MnIn₂S₄ hierarchical photocatalysts with atomically defined junctions for improved photocatalytic activities.

Publications

Direct Z-scheme α-MnO<sub>2</sub>@MnIn<sub>2</sub>S<sub>4</sub> hierarchical photocatalysts with atomically defined junctions for improved photocatalytic activities.

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