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Background: Sustainability aspects have become a main criterion for design next to performance of material and product. Particularly the emerging field of energy storage and conversion is striving towards more sustainable solutions. However, implementing sustainability considerations during the design and development phase of energy materials and products is challenging due to the complexity and broadness of the different dimensions of sustainability. Results: Here, we demonstrate that by using the principles of Safe-and-Sustainable-by-Design (SSbD), a concept can be formulated. This concept served as the basis for selecting and evaluating criteria and performance parameters aimed at enhancing the safety and sustainability aspects of redox active molecules in an organic redox flow battery. Following an iterative approach, the collected data provided valuable insights enabling us to fine-tune and enhance the materials and processes in alignment with the identified parameters. (Social) life cycle assessment focused on the workflow from sourcing, processing and generation of intermediate products to the quinone used in the redox flow batteries and revealed important insights, highlighting critical steps in the process chain. Additionally, we identified two specific points of intervention regarding solvent and quinone choice, based on sustainability parameters. The proposed solvent change resulted in a greener alternative [changed from tetrahydrofuran (THF) to 2-methyl-tetrahydrofuran (MTHF)], and the ecotoxicity testing revealed MGQ and MHQS to be improved options. However, we also faced severe challenges regarding access to reliable LCA data on the raw material sourcing. Conclusion: Taken together, the modified designs led to safer and more sustainable redox active materials for both humans and the environment at lab scale. Implementing the results mentioned above to further expedite the technology will ultimately pave the way to more sustainable energy storage applications. This study proved the value of implementing of an SSbD concept in battery development is the main result of this study. [ABSTRACT FROM AUTHOR]

Wide band-gap organic solar cells are gaining interest due to their applications in emergent light-harvesting technologies such as underwater photovoltaics, multi-junction solar cells, or indoor photovoltaics. In this work, a combinatorial screening approach is used to explore binary combinations of three wide band-gap donors (PTQ10, PM6, and D18) and three wide band-gap acceptors (PMI-FF-PMI, O-IDFBR, and IO-4Cl) deposited from solution in two solvents (CB and CF). In total, 18 combinations are blade-coated with active layers exhibiting a thickness gradient generating solar cells with 12 different thicknesses. PTQ10:IO-4Cl and PTQ10:O-IDFBR are the most efficient blends with efficiencies of 7.31% and 6.87%, respectively. The voltage loss analysis shows that PTQ10-based devices exhibit the lowest non-radiative voltage losses, whereby the PTQ10:O-IDFBR combination has the lowest voltage loss of all studied blends, with a remarkably high open-circuit voltage (Voc) of 1.35 V. Due to their high performance and Voc, PTQ10:O-IDFBR devices were also studied for indoor light harvesting, achieving an efficiency of 22.6% and a Voc of 1.21 V under 560 lux indoor illumination. To the best of our knowledge, this indoor Voc value is the highest achieved in the field of indoor organic photovoltaics. [ABSTRACT FROM AUTHOR]

Species-selective photochemistry is often hampered by overlapping UV-Vis spectra. We overcome this long-standing problem by combined vibrational and electronic excitation as demonstrated by isotopomer selection. The influence of various factors on selectivity is discussed.

A fulgide photoswitch is presented as a novel actinometer for a broad range of wavelengths from the UV to the NIR region (340–700 nm). It is easily accessible and has a robust photochemistry and high fatigue resistance. Its photophysics and photochemistry are described in detail. Quantum yields of photoswitching were measured for a series of wavelengths and standardized against known standards (ferrioxalate actinometry, calibrated photodiode). We also present a method for the precise determination of photoswitching quantum yields by global analysis of the whole spectra and an alternative quick and easy method for rapid determination of photon fluxes. [ABSTRACT FROM AUTHOR]

Donor-acceptor systems, group 14 elements, organic photovoltaics, organometallics, perylene diimides Keywords: donor-acceptor systems; group 14 elements; organic photovoltaics; organometallics; perylene diimides EN donor-acceptor systems group 14 elements organic photovoltaics organometallics perylene diimides 1 1 1 10/18/23 20231013 NES 231013 B Profiting from inorganic modifications b : The organic perylene structure was functionalized with inorganic silicon and germanium atoms. Cover Feature: Silicon- and Germanium-Functionalized Perylene Diimides: Synthesis, Optoelectronic Properties, and Their Application as Non-fullerene Acceptors in Organic Solar Cells (Chem. Eur. J. 57/2023). [Extracted from the article]

Photocages are light-triggerable molecular moieties that can locally release a pre-determined leaving group (LG). Finding a suitable photocage for a particular application may be challenging, as the choice may be limited by for instance the optical or physicochemical properties of the system. Using more than one photocage to release different LGs in a reaction mixture may even be more difficult. In this work an experimental strategy is presented that allows us to hand-pick the release of different LGs, and to do so in any order. This is achieved by using isotopologue photocage-LG mixtures in combination with ultrafast VIbrationally Promoted Electronic Resonance (VIPER) excitation. The latter provides the required molecular selectivity simply by tuning the wavenumber of the used IR pulses to the resonance of a specific photocage isotopologue, as is demonstrated here for the para -hydroxyphenacyl ( p HP) photocage. For spectroscopic convenience, we use isotopologues of the infrared (IR) spectroscopic marker -SCN as different LGs. Especially for applications where fast LG release is required, p HP is found to be an excellent candidate, as free LG formation is observed to occur with a 10 ps lifetime. The devised strategy may open up new complex uncaging applications, where multiple LGs can be formed locally on a short time scale and in any sequence., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Organic solar cells are on the dawn of the next era. The change of focus toward non-fullerene acceptors has introduced an enormous amount of organic n-type materials and has drastically increased the power conversion efficiencies of organic photovoltaics, now exceeding 18%, a value that was believed to be unreachable some years ago. In this Review, we summarize the recent progress in the design of ladder-type fused-ring non-fullerene acceptors in the years 2018-2020. We thereby concentrate on single layer heterojunction solar cells and omit tandem architectures as well as ternary solar cells. By analyzing more than 700 structures, we highlight the basic design principles and their influence on the optical and electrical structure of the acceptor molecules and review their photovoltaic performance obtained so far. This Review should give an extensive overview of the plenitude of acceptor motifs but will also help to understand which structures and strategies are beneficial for designing materials for highly efficient non-fullerene organic solar cells., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)