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AbstractDeriving active pharmaceutical agents from renewable resources is crucial to increasing the economic feasibility of modern biorefineries and promises to alleviate critical supply‐chain dependencies in pharma manufacturing. Our multidisciplinary approach combines research in lignin‐first biorefining, sustainable catalysis, and alternative solvents with bioactivity screening, an in vivo efficacy study, and a structural‐similarity search. The resulting sustainable path to novel anti‐infective, anti‐inflammatory, and anticancer molecules enabled the rapid identification of frontrunners for key therapeutic indications, including an anti‐infective against the priority pathogen Streptococcus pneumoniae with efficacy in vivo and promising plasma and metabolic stability. Our catalytic methods provided straightforward access, inspired by the innate structural features of lignin, to synthetically challenging biologically active molecules with the core structure of dopamine, namely, tetrahydroisoquinolines, quinazolinones, 3‐arylindoles and the natural product tetrahydropapaveroline. Our diverse array of atom‐economic transformations produces only harmless side products and uses benign reaction media, such as tunable deep eutectic solvents for modulating reactivity in challenging cyclization steps.

Bi2S3 has gained considerable attention as a semiconductor for its versatile functional properties, finding application across various fields, and liquid phase exfoliation (LPE) serves as a straightforward method to produce it in nano-form. Till now, the commonly used solvent for LPE has been N-Methyl-2-pyrrolidone, which is expensive, toxic and has a high boiling point. These limitations drive the search for more sustainable alternatives, with water being a promising option. Nonetheless, surfactants are necessary for LPE in water due to the hydrophobic nature of Bi2S3, and organic molecules with amphoteric characteristics are identified as suitable surfactants. However, systematic studies on the use of ionic surfactants in the LPE of Bi2S3 have remained scarce until now. In this work, we used sodium dodecyl sulfate (SDS), sodium dodecylbenzene sulfonate (SDBS) and sodium hexadecyl sulfonate (SHS) as representative species and we present a comprehensive investigation into their effects on the LPE of Bi2S3. Through characterizations of the resulting products, we find that all surfactants effectively exfoliate Bi2S3 into few-layer species. Notably, SDBS demonstrates superior stabilization of the 2D layers compared to the other surfactants, while SHS becomes the most promising surfactant for obtaining products with high yield. Moreover, the resulting nano-inks are used for fabricating films using spray-coating, reaching a fine tuning of band gap by controlling the number of cycles, and paving the way for the utilization of 2D Bi2S3 in optoelectronic devices.

AbstractChemical looping combustion is a highly efficient CO2 separation technology without direct contact between combustion air and fuel. A metal oxide is used as an oxygen carrier in dual fluidized beds to generate clean CO2. The use of biomass is the focus of current research because of the possibility of negative CO2 emissions and the utilization of biogenic carbon. The most commonly proposed OC are natural ores and residues, but complete combustion has not yet been achieved. In this work, the direct utilization of CLC exhaust gas for methane synthesis as an alternative route was investigated, where the gas components CO, CH4 and H2 are not disadvantageous but benefit the reactions in a methanation step. The whole process chain, the coupling of an 80 kWth pilot plant with gas cleaning and a 10 kW fluidized bed methanation unit were for this purpose established. As OC, ilmenite enhanced with limestone was used, combusting bark pellets in autothermal operation at over 1000 °C reaching high combustion efficiencies of up to 91.7%. The fuel reactor exhaust gas was mixed with hydrogen in the methanation reactor at 360 °C and converted with a methane yield of up to 97.3%. The study showed especially high carbon utilization efficiencies of 97% compared to competitor technologies. Based on the experimental results, a scale-up concept study showed the high potential of the combination of the technologies concerning the total efficiency and the adaptability to grid injection. Graphical Abstract

Abstract Hydrogen lines from forming planets are crucial for understanding planet formation. However, the number of planetary hydrogen line detections is still limited. Recent JWST/NIRSpec observations have detected Paschen and Brackett hydrogen lines at TWA 27 B (2M1207b). Although classified as a planetary- mass companison (PMC) rather than a planet due to its large mass ratio to the central star, TWA 27 B’s hydrogen line emissions are expected to be same as the planetary one, given its small mass (≈5M J). We aim to constrain the accretion properties and accretion geometry of TWA 27 B, contributing to our understanding of hydrogen-line emission mechanisms common to both PMCs and planets. We conduct spectral fitting of four bright hydrogen lines (Pa-α, Pa-β, Pa-γ, Pa-δ) with an accretion-shock emission model tailored for forming planets. We estimate the mass accretion rate at M ̇ ≈ 3 × 10 − 9 M J yr − 1 with our fiducial parameters, though this is subject to an uncertainty of up to factor of ten. Our analysis also indicates a dense accretion flow, n ≳ 1013 cm−3 just before the shock, implying a small accretion-shock filling factor f f on the planetary surface (f f ≲ 5 × 10−4). This finding suggests that magnetospheric accretion is occurring at TWA 27 B. Additionally, we carry out a comparative analysis of hydrogen-line emission color to identify the emission mechanism, but the associated uncertainties proved too large for definitive conclusions. This underscores the need for further high-precision observational studies to elucidate these emission mechanisms fully.

AbstractCurrently, Sb2Se3 thin films receive considerable research interest as a solar cell absorber material. When completed into a device stack, the major bottleneck for further device improvement is the open‐circuit voltage, which is the focus of the work presented here. Polycrystalline thin‐film Sb2Se3 absorbers and solar cells are prepared in substrate configuration and the dominant recombination path is studied using photoluminescence spectroscopy and temperature‐dependent current–voltage characteristics. It is found that a post‐deposition annealing after the CdS buffer layer deposition can effectively remove interface recombination since the activation energy of the dominant recombination path becomes equal to the bandgap of the Sb2Se3 absorber. The increased activation energy is accompanied by an increased photoluminescence yield, that is, reduced non‐radiative recombination. Finished Sb2Se3 solar cell devices reach open‐circuit voltages as high as 485 mV. Contrarily, the short‐circuit current density of these devices is limiting the efficiency after the post‐deposition annealing. It is shown that atomic layer‐deposited intermediate buffer layers such as TiO2 or Sb2S3 can pave the way for overcoming this limitation.

Materials and design 254, 114021 (2025). doi:10.1016/j.matdes.2025.114021 Published by Elsevier Science, Amsterdam [u.a.]

Der Klimawandel ist eine globale Herausforderung, wobei die geschätzten Kosten für seine Eindämmung zwischen 1,6 und 3,8 Billionen USD pro Jahr liegen. Als Pionier im Bereich des Klimaschutzes verfügt die Europäische Union über das weltweit umfangreichste Emissionshandelssystem (87 % des globalen Wertes von 865 Mrd. USD im Jahr 2022). Die kumulative Dissertation ist in drei Artikel unterteilt und beschäftigt sich mit der Rolle von forstwirtschaftlichen Kohlenstoffgutschriften sowohl auf den Verpflichtungsmärkten als auch auf den freiwilligen Kohlenstoffmärkten. Dabei werden Potenziale für forstwirtschaftliche Investitionen in diesen beiden Märkten untersucht. Im ersten Artikel wird ein Überblick über die Klimastrategie der Europäischen Union gegeben, wobei der Schwerpunkt auf der Entwicklung des EU-Emissionshandelssystems (EU ETS) und der Rolle von Waldkohlenstoffzertifikaten für Kompensationszwecke sowohl in der Europäischen Union als auch international liegt. Wir argumentieren, dass die Europäische Union weiterhin ein beträchtliches Potenzial der Wälder - insbesondere der tropischen Wälder - als natürliche Kohlenstoffsenken ungenutzt lässt. Im Gegensatz dazu zeigen wir auf, dass die Regulierungsbehörden aus den Erfahrungen und Verbesserungen der Vergangenheit, den Sustainable Carbon Cylces der Europäischen Union und der Fertigstellung und Entwicklung des Regelwerks für Artikel 6 des Pariser Abkommens lernen können. Wir unterbreiten einen Vorschlag zur Änderung der EU-ETS-Verordnung, indem wir die kürzlich im Trilog vereinbarte Gesetzgebung der Europäischen Kommission zur Erhöhung des linearen Reduktionsfaktors von 2,2 % auf 4,2 % auf die Anrechenbarkeit von Waldkohlenstoffgutschriften übertragen, was zu einem zusätzlichen Finanzierungspotenzial für Forstprojekte zur Erhöhung der notwendigen Kohlenstoffsenken führt. Gleichzeitig wird durch die Möglichkeit, in begrenztem Umfang in Neutralisierungsprojekte zu investieren, das Risiko gemindert, dass regulierte Unternehmen bei der Erreichung der Emissionsreduktionsziele überfordert werden. Das Überdenken des Status quo erfordert nicht nur eine Stärkung der Robustheit von Kohlenstoffprojekten, sondern kann auch den Widerstand von politischen Entscheidungsträgern und NGOs überwinden. Emissionsgutschriften aus Wäldern sind in den meisten Emissionshandelssystemen von Bedeutung, da sie ein kosteneffizientes Mittel zum Ausgleich von schwer zu kompensierenden Emissionen darstellen. Bislang war dies im Emissionshandelssystem der Europäischen Union (EU ETS) nicht der Fall. Da das Regelwerk des Pariser Abkommens nun fertiggestellt ist, könnte sich jedoch die Gelegenheit bieten, diesen Flexibilitätsmechanismus in der europäischen Klimapolitik wiederzubeleben. Auf der Grundlage von 24 Experteninterviews untersuchten wir im zweiten Artikel das forstwirtschaftliche Potenzial innerhalb des EU-Emissionshandelssystems über kurz-, mittel- und langfristige Zeiträume. Wir kamen zu dem Ergebnis, dass das Erfüllungssystem bis 2030 blockiert bleiben wird, dass aber langfristig ein Übergang zur Einbeziehung von forstbasierten Entnahmen und Reduktionen wahrscheinlicher ist. Obwohl forstwirtschaftliche Projekte in der EU auf große Zurückhaltung stoßen, herrscht Einigkeit darüber, wie wichtig sowohl technologische Lösungen als auch solche Initiativen für den Klimaschutz sind. Um das Potenzial der Forstwirtschaft in Zukunft voll auszuschöpfen, müssen andere Methoden und Instrumente (z. B. Haftungsregelungen), strengere Rechtsvorschriften für sozioökonomische Faktoren (z. B. Landnutzungsrechte), die Überwindung von Umsetzungshürden (z. B. keine Kompromisse bei der Abschreckung durch Abschwächung) und eine offene politische Haltung eingeführt werden. Diese Studie bietet eine umfassende Perspektive auf die Hindernisse und Potenziale von Forstprojekten im Rahmen des Compliance-Systems der EU, die bei der Wiederaufnahme der Diskussion über die künftige Förderfähigkeit unbedingt berücksichtigt werden muss. Die Ergebnisse der Studie legen nahe, die Hindernisse für die Bereitstellung von Emissionsgutschriften in der nächsten Phase des EU-Emissionshandelssystems ab 2030 unverzüglich zu beseitigen. Der freiwillige Kohlenstoffmarkt (Voluntary Carbon Market, VCM) hat in den letzten Jahren ein beispielloses Wachstum erlebt, das durch die Verpflichtungen der Unternehmen begünstigt wurde. Die künftige Entwicklung hängt jedoch von der Strategie des Pariser Abkommens ab, insbesondere von Artikel 6. Daher werden im dritten Artikel die verschiedenen vorgeschlagenen Mechanismen und ihre Auswirkungen auf den VCM analysiert. Von besonderer Bedeutung ist der Bedarf an entsprechenden Anpassungen (CA) und wie sich diese Anforderung auf den VCM auswirkt. Der "neue" Typ von Kohlenstoffgutschriften, der auf der CoP27 eingeführt wurde, nämlich die "Mitigation Contribution A6.4ERs", wird die Konsolidierung des VCM wahrscheinlich beschleunigen. Auf der Grundlage einer halbsystematischen Überprüfung und von Experteninterviews (N = 20) sprechen die derzeitigen kurzfristigen Aussichten (~2030) für ein weiteres Wachstum des VCM, trotz bestehender Unsicherheiten aufgrund der unvollständigen technischen Details des Rahmens. Darüber hinaus halten die meisten Experten den Artikel 6-Rahmen nach intensiven und gründlichen Verhandlungen für erfolgreich. Mittelfristig (~2030-2045) wird es wahrscheinlich zu einem Marktübergang kommen. Dementsprechend wird der VCM seine Nische finden und das gegenwärtig verwendete Ausgleichsinstrument neu bewerten müssen. Diese Neubewertung muss über eine reine Kohlenstoffperspektive hinausgehen und sich auf die Zusatznutzen konzentrieren, um die Legitimität des VCM zu erhalten. Langfristig (~2045) deuten die Ergebnisse auf einen Rückgang des VCM hin, da er möglicherweise mit Compliance-Märkten kombiniert wird. Die Infrastruktur und die Robustheit der Artikel-6-Regelwerke werden jedoch dazu beitragen, das volle Wachstumspotenzial des VCM zu gewährleisten. Climate change is a global challenge, with estimated mitigation costs ranging from USD1.6 to USD3.8 trillion per year. As a pioneer in climate action, the European Union has the most extensive emissions trading system worldwide (87% of the global value of USD865 billion in 2022). The cumulative PhD thesis is divided into three articles dealing with the role of forest carbon credits in both compliance and voluntary carbon markets as well as investigating further potentials for forest investments in both of these markets. In the first article, we review the European Union's climate strategy, emphasizing the EU Emissions Trading System (EU ETS) development, and the role of forest carbon credits for offsetting purposes, both in the European Union but also internationally. We argue that the European Union continues to leave a significant potential of forests - in particular tropical forests - as natural carbon sinks unattended. In contrast, we reveal that the regulators can learn from the experiences and improvements made in the past, the European Union’s Sustainable Carbon Cylces and the finalization and development of the rulebook for Article 6 of the Paris Agreement. We present a proposal on changes to the EU ETS regulation by converting the European Commission's legislation, recently agreed in the trilogue, to increase the linear reduction factor from 2.2% to 4.2% to the eligibility of forest carbon credits, resulting in additional funding potential for forestry projects to increase necessary carbon sinks. Simultaneously, allowing flexibility of investing to a limited extent in neutralization projects mitigates the risk of overstressing regulated companies to reach the emission reduction targets. The re-thinking of the status quo will not only require strengthening the robustness of carbon projects, but may also overcome the resistance of policy makers and NGOs. Forest-based carbon credits are crucial in most Emissions Trading Schemes as they offer a cost-efficient means of offsetting hard-to-abate emissions. To date, this has not been the case in the European Union Emissions Trading Scheme (EU ETS). However with the Paris Agreement rulebook now finalized, there could be an opportunity to revive this flexibility mechanism in European climate policy. Based on 24 expert interviews, we examined in the second article the forest potential within the EU ETS across short, medium, and long-term time frames. We found that the compliance system will remain blocked until 2030, but there is a greater likelihood of transitioning towards the inclusion of forest-based removals and reductions in the long term. Although forestry projects have faced significant reluctance in the EU, there is unanimous agreement on the importance of both technological solutions and such initiatives for climate protection. To fully leverage the potential of forest activity in the future, it will be necessary to adopt different methods and tools (e.g., liability regimes), stricter legislation on socio-economic factors (e.g., land use rights), overcoming implementation hurdles (e.g., do not compromise deterrence through mitigation), and maintaining an open political stance. This study provides a comprehensive perspective on the barriers and potentials of forestry projects within the compliance system of the EU which is essential to be addressed when re-opening the discussion on future eligibility. The implication of the findings suggest an immediate start to adopt to the barriers for carbon credit readiness in the next phase of the EU ETS beginning of 2030. The voluntary carbon market (VCM) has seen unprecedented growth over the past years, facilitated by corporate commitments. However, future development depends on the Paris Agreement strategy, in particular, Article 6. Therefore, the third article analyzes the various mechanisms suggested and their implications on the VCM. Of particular importance is the need for corresponding adjustments (CA) and how this requirement spills over to the VCM. The “new” type of carbon credits introduced during CoP27, that is, the “mitigation contribution A6.4ERs” will likely accelerate the consolidation of the VCM. Based on a semi-systematic review and expert interviews (N = 20), the current short-term (~2030) prospects support further growth of the VCM despite existing uncertainties caused by the incomplete technical details of the framework. Moreover, after intense and thorough negotiation, most experts deemed the Article 6 framework successful. In the mid-term (~2030-2045), a market transition will likely occur. Accordingly, the VCM will need to find its niche and reassess the current compensation tool used. This reassessment must go beyond a mere carbon perspective and focus on co-benefits to prolong the legitimacy of the VCM. Long-term (~2045) results indicate a decline in the VCM as it potentially combines with compliance markets. However, the infrastructure and robustness of Article 6 rulesets will help to ensure the full growth potential of the VCM.