This work theoretically evaluates light sources currently commercially available for the suitability to drive photoreactions. Comparative evaluation of different light sources reveals significant advantages of light‐emitting diodes (LEDs) in the near UV and visible region, underlining the general superiority of narrow‐band monochromatic light sources for photochemical processes. A generic analysis based on the average volumetric rate of photon absorption shows the limits resulting from physical fundamentals and the importance of the photon fluence rate for process intensification.

Light-driven homogeneous and heterogeneous catalysis require a complex interplay between light absorption, charge separation, charge transfer, and catalytic turnover. Optical and irradiation parameters as well as reaction engineering aspects play major roles in controlling catalytic performance. This multitude of factors makes it difficult to objectively compare light-driven catalysts and provide an unbiased performance assessment. This Scientific Perspective highlights the importance of collecting and reporting experimental data in homogeneous and heterogeneous light-driven catalysis. A critical analysis of the benefits and limitations of the commonly used experimental indicators is provided. Data collection and reporting according to FAIR principles is discussed in the context of future automated data analysis. The authors propose a minimum dataset as a basis for unified collecting and reporting of experimental data in homogeneous and heterogeneous light-driven catalysis. The community is encouraged to support the future development of this parameter list through an open online repository.

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In this work, we present an ew synthetics trategy for fourfold-substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X-ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior.W eo bserved the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation.I nt he presenceo fp oly(dehydroalanine)-graftpoly(ethylene glycol)g raft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo 3 S 13 ] 2À clustersi na queous solution for stable visible light driven hydrogen evolution over three days.

This contribution gives an overview of the general aspects of photochemical reaction engineering, discusses these aspects in the context of rapid prototyping and evaluates the constraints of current additive manufacturing technologies. Subsequently, possible approaches to utilize the benefits of rapid prototyping for process intensification of photochemical reactions are described. Furthermore, the advantageous application of rapid prototyping is demonstrated with the help of four examples.

A simple model for determining potential bottlenecks of a photoreactor setup focusing on the photon fluxes is presented. The application of the concept can reveal optimization potentials and gives insights into the sensitivity of the reactor setup to different optimization possibilities. The introduced model benefits from the concept of using only data already available from optimization studies of the process conditions. Applying the introduced concept to the characterization of a previously developed modular organic light-emitting diode reactor setup revealed great optimization potentials, especially with respect to the external photonic efficiency. Interestingly, the attempt to enhance the external photonic efficiency by increasing the projection area of the reactor did not provide any improvement. This is attributed to a significant influence of reflection and scattering within the setup.

Reproducibility and comparability of photocatalytic experiments are still challenging, owing to the large number of experimental parameters and their comprehensive documentation. To overcome this limitation, a modular, adaptable, and extensible photoreactor platform is reported, which enables experiments under well‐characterized, reproducible conditions. Comparability is ensured by comprehensive photonic characterization with chemical actinometry, radiometry and open documentation of the incident photon fluxes in the reaction vessels for different setups as well as the homogeneity of irradiation in multi‐reactor setups. Comprehensive documentation minimizes the need for repeated photonic characterization when modifying the setups. Experimental reproducibility within and across experiments was evaluated with studies of photocatalytic systems for hydrogen evolution, emphasizing the validity of the concept.

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