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Heterojunctions have received much attention because of their perfect charge-separation effectiveness in improving catalytic/photocatalytic activity, but reproducible formation and nonuniform particle size remain ongoing challenges. Numerous metal-oxide clusters with constructions similar to heterojunction nanoparticles, referred to in this study as intramolecular heterojunction compounds, have now been discovered in the literature and may be potential solutions to the aforementioned challenges. The first section of this critical review introduces the concept of intramolecular heterojunction and the constructions, synthetic methods, and tabulation of selected examples. Catalytic reactions using intramolecular heterojunction compounds are systemically surveyed in the second part, including activation of H2O2 and O2 for selective oxidations, electrocatalytic reductions, photocatalytic water splitting, and CO2 conversion. Finally, future research directions are discussed. In the future, more intramolecular heterojunction compounds may be designed and synthesized following this path, which would undoubtedly benefit research in molecular chemistry and photocatalysis.

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Metal-oxide clusters with semiconductive heterojunction counterparts

Show Author's information Guanyun ZhangYifeng Wang ( )
Key Lab for Colloid and Interface Science of Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China


Heterojunctions have received much attention because of their perfect charge-separation effectiveness in improving catalytic/photocatalytic activity, but reproducible formation and nonuniform particle size remain ongoing challenges. Numerous metal-oxide clusters with constructions similar to heterojunction nanoparticles, referred to in this study as intramolecular heterojunction compounds, have now been discovered in the literature and may be potential solutions to the aforementioned challenges. The first section of this critical review introduces the concept of intramolecular heterojunction and the constructions, synthetic methods, and tabulation of selected examples. Catalytic reactions using intramolecular heterojunction compounds are systemically surveyed in the second part, including activation of H2O2 and O2 for selective oxidations, electrocatalytic reductions, photocatalytic water splitting, and CO2 conversion. Finally, future research directions are discussed. In the future, more intramolecular heterojunction compounds may be designed and synthesized following this path, which would undoubtedly benefit research in molecular chemistry and photocatalysis.

Keywords: catalysis, photocatalysis, heterojunction, metal-oxide cluster, sandwich complexes, S-scheme



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Publication history
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Publication history

Received: 02 September 2022
Revised: 23 October 2022
Accepted: 01 December 2022
Published: 18 January 2023
Issue date: March 2023


© The Author(s) 2023. Polyoxometalates published by Tsinghua University Press.



The authors gratefully acknowledge the National Natural Science Foundation of China (No. 21922605), the Natural Science Foundation of Shandong Province (Nos. GG201809200108 and ZR2019ZD45), the Taishan Scholar Project 454 Foundation of Shandong Province (No. ts20190908) and the Fundamental Research Funds Shandong University (No. 2020QNQT012) for the financial supports.

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