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From Plastic Models to Virtual Reality Headsets: Enhancing Molecular Structure Education for Undergraduate Students
Get PDFThe comprehension of molecular structure is pivotal in chemistry education. Over the past decade, Mahidol University International College has employed various teaching tools for the introductory chemistry laboratory class. This paper outlines our evolutionary shift from traditional tools, such as plastic and plasticine models, to the integration of computer software, and ultimately to augmented reality (AR) and virtual reality (VR) tools—specifically, MoleculARweb and MolecularWebXR developed by École Polytechnique Fédérale de Lausanne researchers. In this paper, we detail the implementation of these tools in our classes and present the outcomes of student surveys. Our instructional focus encompasses VSEPR, Atomic Orbitals, Molecular Orbitals, Skeletal Formula, and Enantiomers. This paper not only serves as a model for educators in general chemistry at secondary school or university levels to incorporate technology into their classrooms but also showcases a collaborative endeavor between Swiss and Thai researchers
Operando Neutron Imaging
Get PDFIn the past, neutron imaging has been the little brother of advanced neutron spectroscopy techniques due to its apparent simplicity. However, this simplicity allows the studying of complex chemical and electrochemical processes and related devices even under harsh reaction conditions such as high pressure, high temperature, corrosive and/or air sensitive environments. We review a number of highly relevant case studies as archetypal examples of modern energy technology; that is heat storage, power-to-X, batteries, fuel cells, and catalysis. The promising results trigger the further development of neutron imaging towards a chemical imaging method
Don’t be Square: Why do Chemistry and Nature Build Hexagons? Chemical Education
No full textThis article distinguishes the role of hexagonal motifs in close-packed solid-state structures and in graphite and graphene; we then illustrate how hexagonal cells in the nests of honey bees and paper wasps minimize construction materials while optimizing space and achieving a robust architecture from delicate material
Chemical Innovation and Agrifood Systems in Switzerland: A Short Perspective of the Sustainable Development Goals
Get PDFChemical innovation plays a key role to support the agrifood system with the final goal to deliver secure, healthy food for a growing population. The underlying link between chemical innovation, agrifood system and the 2030 sustainable agenda may have received less attention than it deserves. Here we provide an overview of the agrifood system and the Sustainable Development Goals (SDGs), alongside distinct aspects of the innovation with a focus on the Swiss reality are presented. Finally, the critical and unspoken role of soil for a wide range of SDGs is underlined. Some major axes on how chemical research and technologies can set new pathway to innovate through soil are discussed
Operando Spectroscopy to Understand Dynamic Structural Changes of Solid Catalysts
Get PDFSolid materials like heterogeneous catalysts are highly dynamic and continuously tend to change when exposed to the reaction environment. To understand the catalyst system under true reaction conditions,operando spectroscopy is the key to unravel small changes, which can ultimately lead to a significant difference in catalytic activity and selectivity. This was also the topic of the 7th International Congress on Operando Spectroscopy in Switzerland in 2023. In this article, we discuss various examples to introduce and demonstrate the importance of this area, including examples from emission control for clean air (e.g. CO oxidation), oxidation catalysis in the chemical industry (e.g. oxidation of isobutene), future power-to-X processes (electrocatalysis, CO2 hydrogenation to methanol), and non-oxidative conversion of methane. All of these processes are equally relevant to the chemical industry. Complementary operando techniques such as X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and Raman spectroscopy were utilized to derive the ultimate structure of the catalyst. The variety of conditions requires distinctly different operando cells that can reach a temperature range of 400–1000 °C and pressures up to 40 bar. The best compromise for both the spectroscopy and the catalytic reaction is needed. As an outlook, we highlight emerging methods such as modulation-excitation spectroscopy (MES) or quick-extended X-ray absorption fine structure (QEXAFS) and X-ray photon in/out techniques, which can provide better sensitivity or extend X-ray based operando studies
X-ray Spectroscopy at the SuperXAS and Debye Beamlines: from in situ to Operando
Get PDFUnderstanding structure–performance relationships are essential for the rational design of new functional materials or in the further optimization of (catalytic) processes. Due to the high penetration depth of the radiation used, synchrotron-based hard X-ray techniques (with energy > 4.5 keV) allow the study of materials under realistic conditions (in situ and operando) and thus play an important role in uncovering structure-performance relationships. X-ray absorption and emission spectroscopies (XAS and XES) give insight into the electronic structure (oxidation state, spin state) and local geometric structure (type and number of nearest neighbor atoms, bond distances, disorder) up to ~5 Å around the element of interest. In this mini review, we will give an overview of the in situ and operando capabilities of the SuperXAS beamline, a facility for hard X-ray spectroscopy, through recent examples from studies of heterogeneous catalysts, electrochemical systems, and photoinduced processes. The possibilities for time-resolved experiments in the time range from ns to seconds and longer are illustrated. The extension of X-ray spectroscopy at the new Debye beamline combined with operando X-ray scattering and diffraction and further developments of time-resolved XES at SuperXAS will open new possibilities after the Swiss Light Source upgrade mid 2025
Protein Engineering and Directed Evolution for Nanocarrier Innovation: Medicinal Chemistry and Chemical Biology Highlights
No full textThe design of nonviral protein-based delivery systems has gained significant attention as an alternative to viral vectors and lipid nanoparticles (LNPs) for gene therapy. While viral vectors offer efficient gene delivery, they present challenges such as immunogenicity and size limitations. LNPs, though pivotal in recent advancements like messenger ribonucleic acid (mRNA)-based vaccines, cause inflammation and exhibit low endosomal escape efficiency. This article explores the development of engineered nonviral protein cages through rational design and directed evolution as an additional nanocarrier option for RNA packaging and delivery. We highlight key advances, including the design and evolution of capsidforming proteins capable of encapsulating and protecting their own encoding mRNA, a critical step in establishing a genotype-phenotype link for evolutionary optimization. Evolved protein cages, such as the I53-50-v4 and NC-4 variants, demonstrate enhanced stability and RNA protection, achieving structural transformations and packaging efficiencies akin to viral systems. The application of directed evolution has expanded the capacity of these nanocarriers enhancing their in vivo stability and biodistribution. This work underscores the potential of evolving nonviral capsids to become customizable platforms for therapeutic gene delivery, while also addressing current limitations in RNA cargo size and tissue targeting specificity. Future directions involve refining these systems to accommodate larger RNAs, and improving immunogenicity properties and dynamic control over cargo release