Due to the development of novel light-sources, methodologies and technologies, photochemistry has seen a remarkable renaissance in academia and industry (Baumann et al., 2014; Bonfield et al., 2020; Cohen et al., 2023). Many photochemical investigations are now routinely performed under continuous-flow conditions in purpose-designed reactors (Loubière et al., 2016; Buglioni et al., 2022). Successful examples of pre-industrial applications have subsequently been developed and realized (Basso and Capurro, 2021; Donnelly and Baumann, 2021; Zhang and Roth, 2023). Likewise, photocalytic materials can be easily incorporated into reactor channels, thus further advancing the potential of flow-photochemistry (Franchi and Amara, 2020; Thomson et al., 2020; Zuliani and Cova, 2021).
This Research Topic comprises of four submissions and highlights recent achievements in photochemical research. Li et al. developed a novel Fe3+-TiO2@CGS three-dimensional photoelectric system and applied it to the degradation of methylene blue. Under optimal operation conditions, the device reached a degradation yield of 99.98% after 60 min of photoelectrical treatment, clearly demonstrating the potential of this technology for the removal of organic contaminants. The constructed photoelectrical degradation reactor was equipped with inlet and outlet points, thus permitting (circulating) flow operation in future studies. Dinter et al. reported on the development of a flexible and affordable microfluidic photochemical flow reactor for rapid prototyping. The fabricated module was first utilized to optimize a photopinacolization reaction and was subsequently transferred to an application with DNA-tagged substrates. The study demonstrated the suitability of the developed modular flow photoreactor as a DNA-encoded library technology (DELT). Meinhardová et al. investigated the role of the lamp type for photocatalytic hydrogen production under batch and flow conditions. The authors initially established the efficiency of six commercial lamps in a batch reactor using a methanol-water solution and a NiO-TiO2 photocatalyst. Using a circulating microphotoreactors system incorporating TiO2 immobilized on borosilicate glass, continuous and reproducible hydrogen generation of 333.7 ± 21.1 µmol H2 or 252.8 ± 16.0 mmol·m−2 was achieved over a period of 168 h. Guo et al. summarized recent advances in catalyst development for the photocatalytic hydrogenation of nitrobenzene to aniline. In contrast to thermal methods, photocatalysis enables the sustainable production of the important platform chemical aniline at room temperature and low hydrogen pressures. Photocatalysts were divided into semiconductors, plasmonic metal-based catalysts and dyes, and the challenges, opportunities and future development prospects of these materials were described. Subsequent immobilization of these photocatalytic materials into flow devices may enable a continuous future production of aniline.
All contributions unambiguously demonstrate the potential and importance of flow-photochemistry and photocatalysis as sustainable and energy-efficient technologies.
Statements
Author contributions
MO: Writing–original draft. LZ: Writing–review and editing. FZ: Writing–review and editing. YS: Writing–review and editing.
Acknowledgments
The guest-editors would like to thank all colleagues and friends who have contributed to this Research Topic.
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher’s note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
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Summary
Keywords
photomicroreactors, flow photochemistry, photocatalysis, scale-up, intelligent flow synthesis
Citation
Oelgemöller M, Zhang L, Zhao F and Su Y (2023) Editorial: Novel technologies for sustainable and energy-efficient flow photochemistry. Front. Chem. 11:1322556. doi: 10.3389/fchem.2023.1322556
Received
16 October 2023
Accepted
19 October 2023
Published
24 October 2023
Volume
11 - 2023
Edited and reviewed by
Kamila Kočí, VŠB-Technical University of Ostrava, Czechia
Updates
Copyright
© 2023 Oelgemöller, Zhang, Zhao and Su.
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*Correspondence: Michael Oelgemöller, michael.oelgemoeller@hs-fresenius.de; Lijing Zhang, zhanglj@dlut.edu.cn; Fang Zhao, fzhao1@ecust.edu.cn; Yuanhai Su, y.su@sjtu.edu.cn
Disclaimer
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.