Search

In diesem Kapitel geht es um den Beitrag der ‚Makroebene‘ des Schulsystems zur Qualität schulischer Prozesse und Ergebnisse. Nach einem Überblick über die Entwicklung des Forschungsbereiches werden im zweiten Abschnitt grundlegende Begriffe geklärt: Wie ist die Makroebene Schulsystem strukturiert und an welchen Merkmalen könnte ihre Qualität abgelesen werden? Danach wird der empirische Forschungsstand an drei Beispielen, der Erforschung von Schulstrukturen, des internationalen Vergleichs von Schüler:innenleistungen sowie der Untersuchung von Governance-Reformen diskutiert.

La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d in its various compositions has proven to be an excellent CO₂-resistant oxygen transport membrane that can be used in plasma-assisted CO₂ conversion. With the goal of incorporating green hydrogen into the CO₂ conversion process, this work takes a step further by investigating the compatibility of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO₂ reduction process into green fuels, like methanol. This requires the La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membranes. The La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d in its various compositions has proven to be an excellent CO₂-resistant oxygen transport membrane that can be used in plasma-assisted CO₂ conversion. With the goal of incorporating green hydrogen into the CO₂ conversion process, this work takes a step further by investigating the compatibility of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO₂ reduction process into green fuels, like methanol. This requires the La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membranes. The La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

To reduce carbon dioxide emissions in energy consumption, there is a need to employ renewable energy carriers with no carbon footprint. Heterogeneous catalysts accelerate chemical reactions or facilitate energetically unfavorable ones to produce such renewable energy carriers. Hydrogen, a promissing primary energy carrier, demands energy for its production, which could be sourced from electric or solar energy via electrolyzers or photocatalysts, respectively. This study focused on synthesizing and characterizing novel nanoparticle-based photocatalytic materials, utilizing CdSe and CdS semiconductors in various forms alongside metal cocatalysts. These nanoparticles can form three-dimensional porous gel-like networks, constructed through shock-freezing or chemical destabilization methods. Photoelectrochemical investigations emphasize the importance of homogeneous metal-semiconductor contact and distributed metal domains for efficient charge carrier separation. Furthermore, the effectiveness of semiconductor and semiconductor-metal hybrid gel structures in photocatalytic hydrogen production is demonstrated. Nanoparticles embedded in hydrogels facilitate efficient photocatalysis, ensuring diffusion within the network without requiring colloidal stability. Platinum as a cocatalyst significantly enhances hydrogen production rates. Moreover, the limiting factors in semiconductor-metal hybrid networks appear to be diffusion within the network or the catalytic reaction itself rather than semiconductor-metal electron transfer. Fine-tuning the distribution of metal domains is crucial for optimizing properties tailored to photocatalytic applications.

Defects among the grains of MOF polycrystalline membranes lead to non-selective gas transport, thereby reducing their selectivity in gas separation. In this work, ZIF-62 polycrystalline membranes with a well-intergrown structure were prepared on MXene-modified supports. Subsequent thermal treatment transformed the membranes into glass membranes, effectively eliminating non-selective defects at grain boundaries. Due to the incorporation of the MXene film and the vertical positioning of the support during the solvothermal process, only a minimal portion of the glass melt infiltrated into the porous support. Across the temperature range of 303 K–423 K and pressure range of 1 bar–3 bar, the ZIF-62 glass membranes showcased superior helium separation property and long-term chemical stability (resistant to CO2 and H2O). The helium permeance reached approximately 51 GPU, with selectivities against N2 and CH4 being 17.4 and 13.9, respectively, outperforming current MOF membranes.

La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d in its various compositions has proven to be an excellent CO₂-resistant oxygen transport membrane that can be used in plasma-assisted CO₂ conversion. With the goal of incorporating green hydrogen into the CO₂ conversion process, this work takes a step further by investigating the compatibility of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO₂ reduction process into green fuels, like methanol. This requires the La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membranes. The La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

After the outbreak of the COVID-19 pandemic, schools had to continuously adapt to new pandemic-related regulations and challenges, including the ad hoc transition to remote learning. According to theories on school improvement and professionalisation, sharing knowledge and experiences with digital learning is helpful when dealing with related issues. However, no existing empirical studies analyse longitudinally how pre-pandemic experiences with sharing knowledge and digital learning impacted perceived professionalisation during the pandemic and how this relationship is mediated both by schools’ strategies to improve learning and by schools’ collective efficacy. For this study N = 280 school principals from Germany, Austria, and German-speaking Swiss cantons participated in two online questionnaires in 2020 and 2021. Results from the structural equation model reveal that schools’ pre-pandemic experiences with knowledge sharing and digital learning are positively indirectly related to the schools’ perceived professionalisation in the first and second year of the pandemic. The relationship is mediated by the schools’ collective efficacy in dealing with the pandemic and the schools’ use of strategies to improve teaching. The results highlight the importance of building school improvement capacity and supporting schools in digital learning to navigate through unexpected emergencies like a pandemic.

La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d in its various compositions has proven to be an excellent CO₂-resistant oxygen transport membrane that can be used in plasma-assisted CO₂ conversion. With the goal of incorporating green hydrogen into the CO₂ conversion process, this work takes a step further by investigating the compatibility of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO₂ reduction process into green fuels, like methanol. This requires the La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membranes. The La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d in its various compositions has proven to be an excellent CO₂-resistant oxygen transport membrane that can be used in plasma-assisted CO₂ conversion. With the goal of incorporating green hydrogen into the CO₂ conversion process, this work takes a step further by investigating the compatibility of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO₂ reduction process into green fuels, like methanol. This requires the La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La₀.₆Ca₀.₄Co₁₋ₓFeₓO₃₋d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membranes. The La₀.₆Ca₀.₄Co₀.₂Fe₀.₈O₃₋d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

For the first time to the best of our knowledge, CeAlO3 nanocrystals with perovskite structure are synthesized by pulsed laser ablation technique. The morphological and optical properties of the obtained CeAlO3 nanocrystals are investigated. This work opens new prospects for the application of laser ablation methods for the generation of perovskite nanocrystals and development of novel nanocomposite structures, which can be applied for the fabrication of perovskite solar cells, scintillation detectors, catalysts, etc.

La0.6Ca0.4Co1–xFexO3–d in its various compositions has proven to be an excellent CO2-resistant oxygen transport membrane that can be used in plasma-assisted CO2 conversion. With the goal of incorporating green hydrogen into the CO2 conversion process, this work takes a step further by investigating the compatibility of La0.6Ca0.4Co1–xFexO3–d membranes with hydrogen fed into the plasma. This will enable plasma-assisted conversion of the carbon monoxide produced in the CO2 reduction process into green fuels, like methanol. This requires the La0.6Ca0.4Co1–xFexO3–d membranes to be tolerant towards reducing conditions of hydrogen. The hydrogen tolerance of La0.6Ca0.4Co1–xFexO3–d (x = 0.8) was studied in detail. A faster and resource-efficient route based on ultrasonic spray synthesis was developed to synthesise the La0.6Ca0.4Co0.2Fe0.8O3–d membranes. The La0.6Ca0.4Co0.2Fe0.8O3–d membrane developed using ultrasonic spray synthesis showed similar performance in terms of its oxygen permeation when compared with the ones synthesised with conventional techniques, such as co-precipitation, sol–gel, etc., despite using 30% less cobalt.

Die kontinuierliche Zusammenarbeit im Kollegium ist ein zentraler Faktor für eine nachhaltige Schulentwicklung. Studien zeigen, dass während der COVID-19-Pandemie eine erhöhte Kooperation in den Schulen stattgefunden hat. Allerdings gibt es keine längsschnittlichen Untersuchungen zu den Bedingungen und Effekten der Kooperation im Kontext der Pandemie. Ziel dieser Studie war es, anhand der Befragung von Schulleiter:innen zu analysieren, wie die Kooperationspraxis von Schulen vor der Pandemie mit der Kooperationspraxis während der Pandemie und der Professionalisierung der Schule im ersten und im zweiten Jahr der Pandemie zusammenhängt. Zudem wird die kollektive Selbstwirksamkeit der Schulen als Mediator dieses Zusammenhangs untersucht. Insgesamt zeigen die Ergebnisse einen positiven Effekt der Kooperationspraktiken von Schulen vor und während der Pandemie auf die wahrgenommene Professionalisierung, aber erst im zweiten Jahr. Die kollektive Selbstwirksamkeit spielt dabei eine vermittelnde Rolle. Daraus lässt sich schließen, dass Kooperation eine wichtige Strategie im Umgang mit den pandemiebezogenen Herausforderungen war und dass es Zeit braucht, bis positive Effekte bei der Professionalisierung spürbar werden.

AbstractMixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H2 and O2 production, CO2 reduction, O2 and H2 separation, CO2 separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Die kontinuierliche Zusammenarbeit im Kollegium ist ein zentraler Faktor für eine nachhaltige Schulentwicklung. Studien zeigen, dass während der COVID-19-Pandemie eine erhöhte Kooperation in den Schulen stattgefunden hat. Allerdings gibt es keine längsschnittlichen Untersuchungen zu den Bedingungen und Effekten der Kooperation im Kontext der Pandemie. Ziel dieser Studie war es, anhand der Befragung von Schulleiter:innen zu analysieren, wie die Kooperationspraxis von Schulen vor der Pandemie mit der Kooperationspraxis während der Pandemie und der Professionalisierung der Schule im ersten und im zweiten Jahr der Pandemie zusammenhängt. Zudem wird die kollektive Selbstwirksamkeit der Schulen als Mediator dieses Zusammenhangs untersucht. Insgesamt zeigen die Ergebnisse einen positiven Effekt der Kooperationspraktiken von Schulen vor und während der Pandemie auf die wahrgenommene Professionalisierung, aber erst im zweiten Jahr. Die kollektive Selbstwirksamkeit spielt dabei eine vermittelnde Rolle. Daraus lässt sich schließen, dass Kooperation eine wichtige Strategie im Umgang mit den pandemiebezogenen Herausforderungen war und dass es Zeit braucht, bis positive Effekte bei der Professionalisierung spürbar werden.

School improvement research is faced with a school teaching staff, which is not a simple homogeneous entity. The compositional attributes of the teaching staff – such as diversity – can have a crucial influence on school processes. Whether the teaching staff is highly fractured, consists of sharply dissociated subgroups, or has shared beliefs, affects the adoption of school improvement programs differently. However, school improvement research has not yet taken into account what different compositions of the teaching staff mean from a methodological viewpoint. It is true that the use of multilevel analysis is standard in school improvement research and that it considers nested school data. However, this method alone only takes averaged measures of teaching staffs into consideration but not their different compositions. In this contribution, we argue that school improvement research has to consider, theoretically and methodologically, how compositional attributes of the teaching staff can be conceptualized. We first discuss some advancements in the conceptualization of group composition from research on small groups and organizations. We then incorporate suggestions for different diversity typologies from small group research to describe the compositional attributes of the teaching staff. Additionally, we address how the composition of the teaching staff influences each teacher differently, depending on the specific position a teacher has within the teaching staff. We further suggest incorporating the Group Actor-Partner Interdependence Model (GAPIM; Kenny, DA, Garcia RL, Small Group Res 43:468–496, 2012) as a methodological approach for assessing these compositional influences. In addition to classic multilevel analysis, the GAPIM also considers the effects of the other teachers on staff and the similarity and dissimilarity of a teacher to the other members of the teaching staff. Finally, we illustrate the possibilities of the theoretical and methodological endorsem

Previous research has revealed that teachers’ regulation activities in schools are most relevant for sustainable school improvement. However, previous studies have severe methodological and theoretical shortcomings. This paper presents the results of a mixed-method case study at four lower secondary schools, in which we developed a framework for understanding regulation activities and processes in schools and analyzed teachers’ regulation activities by using time sampling data of teachers’ performance-related and situation-specific day-to-day activities over 3 weeks. Our results revealed that teachers engage in regulation activities only relatively seldom. Significant differences between teachers were found that are systematically related to the teachers’ specific roles in the school. Teachers rated their regulation activities as especially beneficial for teaching, student learning, and teachers’ learning but as less beneficial for team and school development. Small differences between schools were identified. Further, the results revealed significant correlations between teachers’ perceived benefit of the daily activities and teachers’ daily satisfaction. Based on the results, it can be concluded that the newly developed method appears to be suitable for recording teachers’ daily regulation activities in a (relatively) valid manner and, consequently, for use as a complement to existing instruments. Limitations are discussed, and the need for further research is described.

This book aimed to present innovative designs, measurement instruments, and analysis methods by way of illustrative studies. Through these methodology and design developments, the complexity of school improvement in the context of new governance and accountability measures can be better depicted in future research projects. In this concluding chapter, we discuss what strengths the presented methodologies and designs have and to what extent they do better justice to the multilevel, complex, and dynamic nature of school improvement than previous approaches. In addition, we outline some needs for future research in order to gain new perspectives for future studies.

Schools are continuously confronted with various forms of change, including changes in students’ demographics, large-scale educational reforms, and accountability policies aimed at improving the quality of education. On the part of the schools, this requires sustained adaptation to, and co-development with, such changes to maintain or improve educational quality. As schools are multilevel, complex, and dynamic organizations, many conditions, factors, actors, and practices, as well as the (loosely coupled) interplay between them, can be involved therein (e.g. professional learning communities, accountability systems, leadership, instruction, stakeholders, etc.). School improvement can thus be understood through theories that are based on knowledge of systematic mechanisms that lead to effective schooling in combination with knowledge of context and path dependencies in individual school improvement journeys. Moreover, because theory-building, measuring, and analysing co-develop, fully understanding the school improvement process requires basic knowledge of the latest methodological and analytical developments and corresponding conceptualizations, as well as a continuous discourse on the link between theory and methodology. The complexity places high demands on the designs and methodologies from those who are tasked with empirically assessing and fostering improvements (e.g. educational researchers, quality care departments, and educational inspectorates).

Previous research has revealed that teachers’ regulation activities in schools are most relevant for sustainable school improvement. However, previous studies have severe methodological and theoretical shortcomings. This paper presents the results of a mixed-method case study at four lower secondary schools, in which we developed a framework for understanding regulation activities and processes in schools and analyzed teachers’ regulation activities by using time sampling data of teachers’ performance-related and situation-specific day-to-day activities over 3 weeks. Our results revealed that teachers engage in regulation activities only relatively seldom. Significant differences between teachers were found that are systematically related to the teachers’ specific roles in the school. Teachers rated their regulation activities as especially beneficial for teaching, student learning, and teachers’ learning but as less beneficial for team and school development. Small differences between schools were identified. Further, the results revealed significant correlations between teachers’ perceived benefit of the daily activities and teachers’ daily satisfaction. Based on the results, it can be concluded that the newly developed method appears to be suitable for recording teachers’ daily regulation activities in a (relatively) valid manner and, consequently, for use as a complement to existing instruments. Limitations are discussed, and the need for further research is described.

This book aimed to present innovative designs, measurement instruments, and analysis methods by way of illustrative studies. Through these methodology and design developments, the complexity of school improvement in the context of new governance and accountability measures can be better depicted in future research projects. In this concluding chapter, we discuss what strengths the presented methodologies and designs have and to what extent they do better justice to the multilevel, complex, and dynamic nature of school improvement than previous approaches. In addition, we outline some needs for future research in order to gain new perspectives for future studies.

School improvement research is faced with a school teaching staff, which is not a simple homogeneous entity. The compositional attributes of the teaching staff – such as diversity – can have a crucial influence on school processes. Whether the teaching staff is highly fractured, consists of sharply dissociated subgroups, or has shared beliefs, affects the adoption of school improvement programs differently. However, school improvement research has not yet taken into account what different compositions of the teaching staff mean from a methodological viewpoint. It is true that the use of multilevel analysis is standard in school improvement research and that it considers nested school data. However, this method alone only takes averaged measures of teaching staffs into consideration but not their different compositions. In this contribution, we argue that school improvement research has to consider, theoretically and methodologically, how compositional attributes of the teaching staff can be conceptualized. We first discuss some advancements in the conceptualization of group composition from research on small groups and organizations. We then incorporate suggestions for different diversity typologies from small group research to describe the compositional attributes of the teaching staff. Additionally, we address how the composition of the teaching staff influences each teacher differently, depending on the specific position a teacher has within the teaching staff. We further suggest incorporating the Group Actor-Partner Interdependence Model (GAPIM; Kenny, DA, Garcia RL, Small Group Res 43:468–496, 2012) as a methodological approach for assessing these compositional influences. In addition to classic multilevel analysis, the GAPIM also considers the effects of the other teachers on staff and the similarity and dissimilarity of a teacher to the other members of the teaching staff. Finally, we illustrate the possibilities of the theoretical and methodological endorsem

This open access book discusses challenges in school improvement research and different methodological approaches that have the potential to foster school improvement research. Research on school improvement and accountability analysis places high demands on a study’s design and method. The potential of combining the depth of case studies with the breath of quantitative measures and analyses in a mixed-methods design seems very promising. Consequently, the focus of the book lies on innovative methodological approaches. The book chapters address design, measurement, and analysis developments as well as theoretical and conceptual developments. The relevance of the research presented in the chapters for educational accountability is discussed in the book’s discussion chapter. More specifically, authors present one specific innovative methodological approach and clarify that approach with a concrete example in the context of school improvement, based on empirical data when possible. In this way, this book helps researchers designing complex useful studies.

Schools are continuously confronted with various forms of change, including changes in students’ demographics, large-scale educational reforms, and accountability policies aimed at improving the quality of education. On the part of the schools, this requires sustained adaptation to, and co-development with, such changes to maintain or improve educational quality. As schools are multilevel, complex, and dynamic organizations, many conditions, factors, actors, and practices, as well as the (loosely coupled) interplay between them, can be involved therein (e.g. professional learning communities, accountability systems, leadership, instruction, stakeholders, etc.). School improvement can thus be understood through theories that are based on knowledge of systematic mechanisms that lead to effective schooling in combination with knowledge of context and path dependencies in individual school improvement journeys. Moreover, because theory-building, measuring, and analysing co-develop, fully understanding the school improvement process requires basic knowledge of the latest methodological and analytical developments and corresponding conceptualizations, as well as a continuous discourse on the link between theory and methodology. The complexity places high demands on the designs and methodologies from those who are tasked with empirically assessing and fostering improvements (e.g. educational researchers, quality care departments, and educational inspectorates).

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

The term thermal capacity appears to suggest a storable thermal quantity. However, this claim is not redeemed when thermal capacity is projected onto “heat”, which, like all energy forms, exits only in transit and is not a part of internal energy. The storable thermal quantity is entropy, and entropy capacity is a well-defined physical coefficient which has the advantage of being a susceptibility. The inverse of the entropy capacity relates the response of the system (change of temperature) to a stimulus (change of entropy) such as the fluid level responses to a change in amount of fluid contained in a vessel. Frequently, entropy capacity has been used implicitly, which is clarified in examples of the low-temperature analysis of phononic and electronic contributions to the thermal capacity of solids. Generally, entropy capacity is used in the estimation of the entropy of a solid. Implicitly, the thermoelectric figure of merit refers to entropy capacity. The advantage of the explicit use of entropy capacity comes with a descriptive fundamental understanding of the thermal behaviour of solids, which is made clear by the examples of the Debye model of phonons in solids, the latest thermochemical modelling of carbon allotropes (diamond and graphite) and not least caloric materials. An electrocaloric cycle of barium titanate close to its paraelectric–ferroelectric phase transition is analysed by means of entropy capacity. Entropy capacity is a key to intuitively understanding thermal processes.

A new approach for the development of thermoelectric materials, which focuses on a high-power factor instead of a large figure of merit zT, has drawn attention in recent years. In this context, the thermoelectric properties of Cu-Ni-based alloys with a very high electrical conductivity, a moderate Seebeck coefficient, and therefore a high power factor are presented as promising low-cost alternative materials for applications aiming to have a high electrical power output. The Cu-Ni-based alloys are prepared via an arc melting process of metallic nanopowders. The heavy elements tin and tungsten are chosen for alloying to further improve the power factor while simultaneously reducing the high thermal conductivity of the resulting metal alloy, which also has a positive effect on the zT value. Overall, the samples prepared with low amounts of Sn and W show an increase in the power factor and figure of merit zT compared to the pure Cu-Ni alloy. These results demonstrate the potential of these often overlooked metal alloys and the utilization of nanopowders for thermoelectric energy conversion.

The rapid development of nanotechnology and its applications in medicine has provided the perfect solution against a wide range of different microbes, especially antibiotic-resistant ones. In this study, a one-step approach was used in preparing silver nanoparticles (AgNPs) by mixing silver nitrate with hot Hypericum perforatum (St. John’s wort) aqueous extract under high stirring to prevent agglomeration. The formation of silver nanoparticles was monitored by continuous measurement of the surface plasma resonance spectra (UV-VIS). The effect of St. John’s wort aqueous extract on the formation of silver nanoparticles was evaluated and fully characterized by using different physicochemical techniques. The obtained silver nanoparticles were spherical, monodisperse, face-centered cubic (fcc) crystal structures, and the size ranges between 20 to 40 nm. They were covered with a capping layer of organic compounds considered as a nano dimension protective layer that prevents agglomeration and sedimentation. AgNPs revealed antibacterial activity against both tested Gram-positive and Gram-negative bacterial strains causing the formation of 13–32 mm inhibition zones with MIC 6.25–12.5 µg/mL; Escherichia coli strains were resistant to tested AgNPs. The specific growth rate of S. aureus was significantly reduced due to tested AgNPs at concentrations ≥½ MIC. AgNPs did not affect wound migration in fibroblast cell lines compared to control. Our results highlighted the potential use of AgNPs capped with plant extracts in the pharmaceutical and food industries to control bacterial pathogens’ growth; however, further studies are required to confirm their wound healing capability and their health impact must be critically evaluated

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Mixed ionic-electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H2 and O2 production, CO2 reduction, O2 and H2 separation, CO2 separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar-driven evaporation and energy-saving regeneration as well as electrolyzer cells for power-to-X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state-of-the-art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry-oriented research toward commercialization of MIEC membranes for different applications.

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Mixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H₂ and O₂ production, CO₂ reduction, O₂ and H₂ separation, CO₂ separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

The impact of low-pressure treatment on the crystal structure, morphology, and chemical composition of ettringite, due to their major importance with respect to processability (i.a., dry-ing conditions) and to the analysis of ettringite-containing samples, is examined utilizing X-ray diffraction, thermogravimetric analysis, Raman spectroscopy, and environmental scanning electron microscopy. Synthetic ettringite was treated for various durations (5 min up to 72 h) and at two different levels of low-pressure (4.0 mbar and 60 µbar). Evaluation showed a correlation between the procedural parameters (time and pressure), the chemical composition, and the morphology of ettringite. The experiments reveal that, when exposed to 4 mbar pressure, nearly no changes occur in the ettringite’s morphology, whereas the crystals undergo swelling and slight deformations at very low pressures (60 µbar and 35.3 nbar), which is attributed to the loss of bound water and the partial transformation from ettringite to quicklime, anhydrite, and calcium aluminate. Furthermore, the strongly dehydrated ettringite shows the same morphology.

Item does not contain fulltext, School improvement and educational change can be facilitated by learning through reflection, as this allows teachers to discover ways to develop and adapt to change. Higher levels of engagement in reflection have been found to be beneficial, but it is unclear from which everyday routine in engagement in reflection higher levels arise, and thus whether occasions to make knowledge explicit should be organized with a certain constancy. In this study, we therefore used a conceptualization of teacher learning through reflection as a situated and dynamic process in which available environmental information, learning activities, and professional practices are interconnected, and co-develop. Seventeen Dutch Vocational Education and Training teachers participated over a period of 5 months. We explored the use of daily and monthly logs as measurement instruments and Recurrence Quantification Analysis (RQA) as the analysis technique applied to the time-series generated from the daily logs. The findings indicated that teachers who make information from their working environment explicit more are also able to make new insights explicit more. The routine with which teachers make information explicit was found to be mostly unrelated to making new insights explicit. To reach their levels of engagement in reflection, some teachers organized opportunities to reflect with determined intervals, others seemed to recognize those opportunities as the working environment provided them, and some used a combination thereof. Moreover, the use of daily and monthly logs seemed to fit better to some participants than others. Only sometimes does organizing constancy in engagement in reflection seem to relate to the levels thereof. This study provides an example of how logs and RQA can be adopted to tap into professional learning as a dynamic and situated process in support of school improvement and educational change.

Item does not contain fulltext, School improvement and educational change can be facilitated by learning through reflection, as this allows teachers to discover ways to develop and adapt to change. Higher levels of engagement in reflection have been found to be beneficial, but it is unclear from which everyday routine in engagement in reflection higher levels arise, and thus whether occasions to make knowledge explicit should be organized with a certain constancy. In this study, we therefore used a conceptualization of teacher learning through reflection as a situated and dynamic process in which available environmental information, learning activities, and professional practices are interconnected, and co-develop. Seventeen Dutch Vocational Education and Training teachers participated over a period of 5 months. We explored the use of daily and monthly logs as measurement instruments and Recurrence Quantification Analysis (RQA) as the analysis technique applied to the time-series generated from the daily logs. The findings indicated that teachers who make information from their working environment explicit more are also able to make new insights explicit more. The routine with which teachers make information explicit was found to be mostly unrelated to making new insights explicit. To reach their levels of engagement in reflection, some teachers organized opportunities to reflect with determined intervals, others seemed to recognize those opportunities as the working environment provided them, and some used a combination thereof. Moreover, the use of daily and monthly logs seemed to fit better to some participants than others. Only sometimes does organizing constancy in engagement in reflection seem to relate to the levels thereof. This study provides an example of how logs and RQA can be adopted to tap into professional learning as a dynamic and situated process in support of school improvement and educational change.

The manufacturing technology of thermoelectric materials is laborious and expensive often including complex and time-intensive preparation steps. In this work, a laser sintering process of the oxide-based thermoelectric material Ca3Co4O9 is investigated. Samples based on spray-coated Ca3Co4O9 were prepared and subsequently sintered under various laser parameters and investigated in terms of the microstructure and thermoelectric properties. Here, the combination of laser sintering and subsequent thermal sintering proved to be a promising concept for the preparation of thermoelectric films. Laser sintering can thus make a great contribution in improving the processing of thermoelectric materials, especially when films are applied that cannot be sintered under pressure. © 2021 The Authors. Chemie Ingenieur Technik published by Wiley-VCH GmbH

This contribution focuses on the green synthesis of silver nanoparticles (AgNPs) with a size < 100 nm for potential medical applications by using silver nitrate solution and Hypericum Perforatum L. (St John’s wort) aqueous extracts. Various synthesis methods were used and compared with regard to their yield and quality of obtained AgNPs. Monodisperse spherical nanoparticles were generated with a size of approximately 20 to 50 nm as elucidated by different techniques (SEM, TEM). XRD measurements showed that metallic silver was formed and the particles possess a face-centered cubic structure (fcc). SEM images and FTIR spectra revealed that the AgNPs are covered by a protective surface layer composed of organic components originating from the plant extract. Ultraviolet-visible spectroscopy, dynamic light scattering, and zeta potential were also measured for biologically synthesized AgNPs. A potential mechanism of reducing silver ions to silver metal and protecting it in the nanoscale form has been proposed based on the obtained results. Moreover, the AgNPs prepared in the present study have been shown to exhibit a high antioxidant activity for 2, 2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation, and super oxide anion radical and 2,2-diphenyl-1-picrylhydrazyl. Synthesized AgNPs showed high cytotoxicity by inhibiting cell viability for Hela, Hep G2, and A549 cells.

Poly(3,4-ethylenedioxythiophene) (PEDOT) plays a key role in the field of electrically conducting materials, despite its poor solubility and processability. Various molecules and polymers carrying sulfonic groups can be used to enhance PEDOT’s electrical conductivity. Among all, sul-fonated polyarylether sulfone (SPAES), prepared via homogenous synthesis with controlled degree of sulfonation (DS), is a very promising PEDOT doping agent. In this work, PEDOT was synthesized via high-concentration solvent-based emulsion polymerization using 1% w/w of SPAES with different DS as dopant. It was found that the PEDOT:SPAESs obtained have improved solubility in the chosen reaction solvents, i.e., N, N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, and N-methyl-2-pyrrolidone and, for the first time, the role of doping agent, DS and polymerization solvents were investigated analyzing the electrical properties of SPAESs and PEDOT:SPAES samples and studying the different morphology of PEDOT-based thin films. High DS of SPAES, i.e., 2.4 meq R-SO3− × g−1 of polymer, proved crucial in enhancing PEDOT’s electrical conductivity. Furthermore, the DMSO capability to favor PEDOT and SPAES chains rearrangement and interaction results in the formation of a polymer film with more homogenous morphology and higher conductivity than the ones prepared from DMAc, DMF, and NMP. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

In this work, mixing and co-gelation of Au nanoparticles (NPs) and highly luminescent CdSe/CdS core/shell nanorods (NRs) are used as tools to obtain noble metal particle-decorated macroscopic semiconductor gel networks. The hybrid nature of the macrostructures facilitates the control over the optical properties: while the holes are trapped in the CdSe cores, the connected CdSe/CdS NRs support the mobility of excited electrons throughout the porous, hyperbranched gel networks. Due to the presence of Au NPs in the mixed gels, electron trapping in the gold NPs leads to a suppressed radiative recombination, namely, quenches the fluorescence in certain fragments of the multicomponent gel. The extent of fluorescence quenching can be influenced by the quantity of the noble metal domains. The optical properties are monitored as a function of the NR:NP ratio of a model system CdSe/CdS:Au. By this correlation, it demonstrates that the spatial extent of quenching initiated by a single Au NP exceeds the dimensions of one NR, which the Au is connected to (with a length of 45.8 nm ± 4.1 nm) and can reach the number of nine NRs per Au NP, which roughly corresponds to 400 nm of total electron travel distance within the network structure.

The oxide materials Ca3Co4O9 and Na2Ca2Nb4O13 were combined in a new ceramic composite with promising synergistic thermoelectric properties. Both compounds show a plate-like crystal shape and similar aspect ratios but the matrix material Ca3Co4O9 with lateral sizes of less than 500 nm is about two orders of magnitude smaller. Uniaxial pressing of the mixed compound powders was used to produce porous ceramics after conventional sintering. Reactions between both compounds and their compositions were thoroughly investigated. In comparison to pure Ca3Co4O9, mixing with low amounts of Na2Ca2Nb4O13 proved to be beneficial for the overall thermoelectric properties. A maximum figure-of-merit of zT = 0.32 at 1073 K and therefore an improvement of about 19% was achieved by the ceramic composites.

In this work, mixing and co-gelation of Au nanoparticles (NPs) and highly luminescent CdSe/CdS core/shell nanorods (NRs) are used as tools to obtain noble metal particle-decorated macroscopic semiconductor gel networks. The hybrid nature of the macrostructures facilitates the control over the optical properties: while the holes are trapped in the CdSe cores, the connected CdSe/CdS NRs support the mobility of excited electrons throughout the porous, hyperbranched gel networks. Due to the presence of Au NPs in the mixed gels, electron trapping in the gold NPs leads to a suppressed radiative recombination, namely, quenches the fluorescence in certain fragments of the multicomponent gel. The extent of fluorescence quenching can be influenced by the quantity of the noble metal domains. The optical properties are monitored as a function of the NR:NP ratio of a model system CdSe/CdS:Au. By this correlation, it demonstrates that the spatial extent of quenching initiated by a single Au NP exceeds the dimensions of one NR, which the Au is connected to (with a length of 45.8 nm ± 4.1 nm) and can reach the number of nine NRs per Au NP, which roughly corresponds to 400 nm of total electron travel distance within the network structure.

Hybrid semiconductor-based nanocrystals (NCs) are generally synthesized in organic media prior to their assembly into catalytically promising nanostructures via multistep methods. Here, a tunable, easy-to-adapt and versatile approach for the preparation of hybrid nanoparticle networks from aqueous nanocrystal solutions is demonstrated. The networks consist of interconnected semiconductor NC backbones (made of CdSe/CdS dot-in-rods or core/crown nanoplatelets) decorated with noble metal (Au and Pt) or with metal-based domains (Co2+ and Ni2+) demonstrating a powerful synthetic control over a variety of hybrid nanostructures. The deposition of the domains and the formation of the network take place simultaneously (one-step method) at room temperature in dark conditions without any external trigger. Beside the in-depth structural characterization of the gel-like hybrid networks, the wavelength-dependent optical features are studied to reveal an efficient charge carrier separation in the systems and a controllable extent of fluorescence quenching through the domain sizes. Photoluminescence quantum yields and decay dynamics highlight the importance of fine-tuning the conduction band/Fermi level offset between the semiconductors and the various deposited metals playing central role in the electron–hole separation processes. This procedure provides a novel platform toward the preparation of photo(electro)catalytically promising hybrid nanostructures (acetogels and xerogels) without the need of presynthetic hybrid particle design.

Ferroelectric materials with engineered thus visible-range optical band gaps are increasingly researched in recent years, triggering potentially new applications in solar cells, opto-ferroelectric devices, multifunctional sensors, and multisource energy harvesters. To date, most band gap engineered ferroelectrics have been discovered in form of ceramics fabricated via the solid-state route. Like other functional counterparts further research of these materials into nanoscale developments, e.g., nanocomposites and thin films, demands nanofabrication methods to be investigated. An emerging band gap engineered ferroelectric composition, (K,Na,Ba)(Ni,Nb)O3−δ (KNBNNO), discovered with solid-state route has allured research for novel applications as mentioned above. However, its nanofabrication via wet chemical routes has rarely been reported. In this paper, sol–gel method is used to fabricate KNBNNO nanoparticles. The developed method can successfully form the target perovskite phases, and is able to reduce the particle size from 300 to 400 nm made via the solid-state reaction to about 100 nm. In addition, the distributed particle size in the synthesized solutions averages at 4–6 nm, making the method suitable for potential thin film fabrication. Therefore, this paper offers a nanofabrication option to the emerging KNBNNO for prospective nanoscale research.

Besides the material research in the field of thermoelectrics, the way from a material to a functional thermoelectric (TE) module comes alongside additional challenges. Thus, comprehension and optimization of the properties and the design of a TE module are important tasks. In this work, different geometry optimization strategies to reach maximum power output or maximum conversion efficiency are applied and the resulting performances of various modules and respective materials are analyzed. A Bi2Te3-based module, a half-Heusler-based module, and an oxide-based module are characterized via FEM simulations. By this, a deviation of optimum power output and optimum conversion efficiency in dependence of the diversity of thermoelectric materials is found. Additionally, for all modules, the respective fluxes of entropy and charge as well as the corresponding fluxes of thermal and electrical energy within the thermolegs are shown. The full understanding and enhancement of the performance of a TE module may be further improved

Several critical issues, such as the shuttling effect and the sluggish reaction kinetics, exist in the design of high-performance lithium–sulfur (Li-S) batteries. Here, it is reported that nitrogen doping can simultaneously and significantly improve both the immobilization and catalyzation effects of Co9S8 nanoparticles in Li-S batteries. Combining the theoretical calculations with experimental investigations, it is revealed that nitrogen atoms can increase the binding energies between LiPSs and Co9S8, and as well as alleviate the sluggish kinetics of Li-S chemistry in the Li2S6 cathode. The same effects are also observed when adding N-Co9S8 nanoparticles into the commercial Li2S cathode (which has various intrinsic advantages, but unfortunately a high overpotential). A remarkable improvement in the battery performances in both cases is observed. The work brings heteroatom-doped Co9S8 to the attention of designing high-performance Li-S batteries. A fundamental understanding of the inhibition of LiPSs shuttle and the catalytic effect of Li2S in the newly developed system may encourage more effort along this interesting direction. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The basic principles of thermoelectrics rely on the coupling of entropy and electric charge. However, the long-standing dispute of energetics versus entropy has long paralysed the field. Herein, it is shown that treating entropy and electric charge in a symmetric manner enables a simple transport equation to be obtained and the power conversion and its efficiency to be deduced for a single thermoelectric material apart from a device. The material’s performance in both generator mode (thermo-electric) and entropy pump mode (electro-thermal) are discussed on a single voltage-electrical current curve, which is presented in a generalized manner by relating it to the electrically open-circuit voltage and the electrically closed-circuited electrical current. The electrical and thermal power in entropy pump mode are related to the maximum electrical power in generator mode, which depends on the material’s power factor. Particular working points on the material’s voltage-electrical current curve are deduced, namely, the electrical open circuit, electrical short circuit, maximum electrical power, maximum power conversion efficiency, and entropy conductivity inversion. Optimizing a thermoelectric material for different working points is discussed with respect to its figure-of-merit zT and power factor. The importance of the results to state-of-the-art and emerging materials is emphasized.

Several critical issues, such as the shuttling effect and the sluggish reaction kinetics, exist in the design of high-performance lithium–sulfur (Li-S) batteries. Here, it is reported that nitrogen doping can simultaneously and significantly improve both the immobilization and catalyzation effects of Co9S8 nanoparticles in Li-S batteries. Combining the theoretical calculations with experimental investigations, it is revealed that nitrogen atoms can increase the binding energies between LiPSs and Co9S8, and as well as alleviate the sluggish kinetics of Li-S chemistry in the Li2S6 cathode. The same effects are also observed when adding N-Co9S8 nanoparticles into the commercial Li2S cathode (which has various intrinsic advantages, but unfortunately a high overpotential). A remarkable improvement in the battery performances in both cases is observed. The work brings heteroatom-doped Co9S8 to the attention of designing high-performance Li-S batteries. A fundamental understanding of the inhibition of LiPSs shuttle and the catalytic effect of Li2S in the newly developed system may encourage more effort along this interesting direction. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The room-temperature (RT) 57Fe Mössbauer spectra of the La3Ni2–xFexO7±δ oxide solid solutions of Ruddlesden-Popper-type (x = 0.05, 0.10) reveal two doublets for Fe3+ ions in octahedral coordination by oxygen. The existence of two inequivalent sites for Fe at RT is at variance with the space groups Fmmm and Cmcm (Amam) which have been reported for La3Ni2O7±δ. This unexpected finding is discussed in connection with Patterson analyses and Rietveld refinements of powder XRD data for x = 0, 0.05, and 0.10. Alternative structural models have been proposed which can explain the spectroscopic findings and which are compatible with the results from X‑ray diffraction.