Polymer photocatalysts for solar-to-chemical energy conversion

Abstract

Solar-to-chemical energy conversion for the generation of high-energy chemicals is one of the most viable solutions to the quest for sustainable energy resources. Although long dominated by inorganic semiconductors, organic polymeric photocatalysts offer the advantage of a broad, molecular-level design space of their optoelectronic and surface catalytic properties, owing to their molecularly precise backbone. In this Review, we discuss the fundamental concepts of polymeric photocatalysis and examine different polymeric photocatalysts, including carbon nitrides, conjugated polymers, covalent triazine frameworks and covalent organic frameworks. We analyse the photophysical and physico-chemical concepts that govern the photocatalytic performance of these materials, and derive design principles and possible future research directions in this emerging field of ‘soft photocatalysis’.

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Fig. 1: Inorganic semiconductor and organic semiconductor photocatalysis.
Fig. 2: Synthesis and structural features of organic polymers.
Fig. 3: Light absorption and charge-carrier dynamics in carbon nitrides.
Fig. 4: Modulation of light absorption and charge separation in π-conjugated organic polymers.
Fig. 5: Oligomers as photocatalysts.
Fig. 6: Molecular tunability of covalent organic framework photocatalysts.
Fig. 7: Single-site covalent organic framework photocatalyst for CO2 photoreduction.

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Acknowledgements

Financial support by an ERC Starting Grant (project COF Leaf, grant number 639233), the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) project number 358283783–SFB 1333, the Max Planck Society, the Cluster of Excellence e-conversion and the Center for NanoScience (CeNS) is gratefully acknowledged.

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T.B., F.P. and J.K. wrote the manuscript, along with contributions from B.V.L. and B.P.B. All authors read and commented on the final manuscript.

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Correspondence to Bettina V. Lotsch.

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Banerjee, T., Podjaski, F., Kröger, J. et al. Polymer photocatalysts for solar-to-chemical energy conversion. Nat Rev Mater (2020). https://doi.org/10.1038/s41578-020-00254-z

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