Chimia最新文献

In this perspective, we will discuss the impact of some of the most recent advancements in materials discovery, particularly focusing on the role of robotics, artificial intelligence, and self-driving laboratories, as well as their implications for the Swiss research landscape. While it seems timely to aim for broad, revolutionary breakthroughs in this field, we argue that more incremental steps - such as, for example, fully automatic grinding of solid powders or fully automated Rietveld refinements - may have a more significant impact on materials discovery, at least in the short run. In the center of these considerations is how small, interdisciplinary groups can drive significant progress by contributing targeted innovations, such as e.g.robotic sample preparation or computational predictions. Additionally, given the large investments that are necessary for future infrastructures in materials discovery, we discuss the potential case for the establishment - in the long run - of a national infrastructure, a Swiss Materials Discovery Lab, to support automated material synthesis and advanced characterization, ultimately accelerating innovation in both academic and industrial settings.

Demand for lithium is expected to quadruple by the end of the decade. Without new sources of production, the supply-demand curve is expected to invert. Traditional geological reserves will not be able to meet the anticipated gap, thus unconventional sources of lithium will need to be utilized, setting the stage for fierce competition for perhaps the most critical of mineral resources required for the energy transition. Direct Lithium Extraction refers to the umbrella of technologies being developed to access lithium from unconventional sources. Electrochemical extraction offers significant promise for its selectivity and low operating cost when coupled with renewable energy. This review aims to describe materials and process design considerations for electrochemical extraction of lithium from aqueous sources with a specific emphasis on ζ-V2O5 designed in our research group as an insertion host. We point to specific strategies for improving capacity and selectivity for electrochemical lithium extraction based on materials design across length scales. Strategies range from site-selective modification of insertion hosts to controlled tortuosity of ion diffusion pathways in porous electrode architectures. Electrochemical lithium extraction from unconventional sources stands poised to be a linchpin of a sustainable economy when coupled with cleaning of wastewater, hydrogen generation, and recovery of ancillary critical metals.

The stereoregularity of a polymer plays a key role in determining its properties. While stereocontrol can easily be achieved in coordination and ionic polymerization, it remains a challenge with radical polymerization. Considering the ubiquity and versatility of radical polymerization, significant efforts have been made over the past 50 years to address this issue. In this mini review, we highlight some of the strategies that have been developed to enable stereospecific radical polymerization, from the use of Lewis acid additives to the application of high electric fields. We hope that this review will provide the reader with a comprehensive overview of the current state of the art and equip them with the foundational knowledge needed to explore new avenues in this domain.

Ten years after the discovery of colloidal lead halide perovskite nanocrystals (LHP NCs), the field has witnessed substantial progress in synthetic methods, understanding of their surface chemistry and unique optical properties, precise control over NC size, shape, and composition. Ligand engineering, particularly with cationic and zwitterionic head groups, massively enhanced NC stability, compatibility with organic solvents, and photoluminescence efficiency. These breakthroughs allowed for the self-assembly of monodisperse NCs into complex long-range ordered superlattices and enabled the exploration of collective optical phenomena, such as superfluorescence. The development of low-cost scalable approaches like microfluidic systems and mechanochemical synthesis paved the way for the commercialization of LHP NCs, particularly for the down-conversion films in blue-backlit LCDs and as thermally-efficient color converters in pixelated displays. This review aims to trace the journey of these advancements, focusing on contributions from Switzerland, and outline future directions in this rapidly evolving field, such as quantum light sources, photocatalysis, etc.

Photon interconversion promises to alleviate thermalization losses for high energy photons and facilitates utilization of sub-bandgap photons - effectively enabling the optimal use of the entire solar spectrum. However, for solid-state device applications, the impact of intermolecular interactions on the energetic landscape underlying singlet fission and triplet-triplet annihilation upconversion cannot be neglected. In the following, the implications of molecular arrangement, intermolecular coupling strength and molecular orientation on the respective processes of solid-state singlet fission and triplet-triplet annihilation are discussed.

Food and beverage production generates enormous amounts of spent residues in the form of pomaces, pulps, grains, skins, seeds, etc. Although these sidestreams remain nutritious, their conversion to foods can be complicated by issues of digestibility and processing, particularly when the residues are wet and therefore highly susceptible to microbial degradation. Ideally, these sidestreams could be stabilized and then re-circulated into food, instead of being diverted to waste, animal feed, or biofuels. Indeed, the end-of-life of our food crops is increasingly important to consider in the context of circularity, ensuring that land, water, and chemical inputs to agriculture are sustainable. In the context of wet byproducts from the food industry, we discuss two separate case studies that look at how to valorize and extend the longevity of nutritionally-rich but underutilized sidestreams. The first study examines the fermentation of okara into an edible tempeh-like cake, while the second investigates ProSeed's approach to drying and valorizing brewer's spent grain. We conclude with some words on the nuance and challenges involved in saving from waste the highly perishable but nutritious side products of current food and beverage production.

In this article, we provide an overview of hydrogen storage materials, taking our previous results as examples. Towards the end of the paper, we present a case study in order to highlight the effects of substitutional alloying, compositional additives, and nanostructuring on the hydrogen sorption properties of magnesium-based intermetallics. Specifically, partial substitution of Mg by Li and d-elements by p-elements leads to structural changes, inducing disorder and the formation of high-entropy alloys. Our approach showcases the methodology to enhance the H2-capacity and to provide a positive boost to the H2-storage performance, including lower temperatures of H2 desorption, better thermodynamics and kinetics, lower temperatures of hydrogen uptake/ release for Metal-Hydride Hydrogen Storage (MHHS) systems and higher capacity of anodes for Metal-Hydride batteries (MHB) together with lower prices of raw materials.

Atmospheric aerosols can be emitted directly as particles or formed in the atmosphere from phase transitions of gaseous compounds with low enough vapor pressure. During their lifecycle in the atmosphere, aerosols undergo multiphase changes, altering chemical composition, reactivity, physical and optical properties, ultimately influencing how they impact climate, human health and ecosystems. The understanding of the chemical processes in the atmosphere is crucial to assess these effects. Here we provide a brief overview on relevant aerosol chemical processes and measurement techniques with no claim to completeness and describe the Swiss contribution to the European infrastructure ACTRIS for long-term monitoring and its relevance for the research field.

Arctic coasts cover more than 101,000 km and emulsify terrestrial, marine and socio-economic ecosystems. All three components produce specific emissions that contribute to the mix of atmospheric constituents, which are processed and dispersed in the coastal atmosphere to contribute to cloud formation through cloud condensation nuclei and ice nucleating particles. Clouds strongly influence the coastal energy balance. Importantly, Arctic coastal ecosystems are exposed to multiple pressures such as the warming atmosphere and ocean, the thawing cryosphere and the expanding anthropogenic activities. This means that coastal emissions and atmospheric processes are in constant evolution. Given the large area covered by coasts and the mix of emission sources, coastal aerosol processes deserve quantification to better understand their role in accelerated Arctic climate change.