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- Beräkningskemisk modellering för fotoemissionsspektroskopi samt nedbrytningsmekanismer för batterielektrolyter(2026) Grut, Erica; Linder, Cornelia; Janemyr, Noel; Richardsson, Axel; Olofsson, TorComputational chemical modeling for photoemission spectroscopy and decomposition products of battery electrolytes. The project examines how quantum chemical methods can simulate x-ray photoelectron spectroscopy (XPS) peaks and theoretically analyze decomposition mechanisms for the electrolyte molecules etyhlene carbonate (EC), propylene carbonate (PC) and fluoroet hylene carbonate (FEC) in lithium-ion batteries. By benchmarking quantum chemical methods against experimental data, suitable methods for simulating XPS-spectra and the reaction energetics of the electrolyte decomposition products that balance accuracy and computational cost could be identified. XPS-simulations of ethyltrifluoroacetate (ESCA) show good agreement with experi mental reference data. Simulations of EC and PC were also made, which exhibit good conformity with values within 0.5 eV of the experimental values. These simulations support computational methods as a reliable way of predicting binding-energies. Further on, electrochemical reaction pathways were analyzed with transition state the ory and Marcus theory. The results shows that EC, PC and FEC has similar decompo sition mechanisms in lithium-ion batteries during operation. Additionally, results show that different calculation methods predict different favorable reactions, where Marcus theory generally predicts lower activation barriers and therefore more favorable electron transfer reactions. Explicit transition state calculations tend to predict high activation barriers, especially in ring-opening reaction steps where the reorganization energies are the driving force. It also indicates that FEC has a higher reduction potential and a faster reduction compared to EC and PC, which supports its function as an additive to enhance the solid electrolyte interface (SEI)-formation. In conclusion, this project shows how quantum chemical methods can be versatile in understanding both XPS-spectra and decomposition mechanisms in lithium-ion battery electrolytes with specific usage in analysis of SEI-formation.
- Lokal struktur hos metallhalidperovskiter undersökt med vibrationsspektroskopi(2026) Curkic, Elma; Eidstedt, Lina; Loman, Janna; Swartz, EmiliaLocal Structure in Metal Halide Perovskites studied with Vibrational Spectroscopy The rapid development of metal halide perovskites has during the last decade positio ned the material as one of the most promising candidates for future energy technology such as solar cell technology, light emitting diodes, and photodetectors. Because metal halide perovskites are very flexible and in combination with the ease of synt hesizing the material, they are particularly attractive to use for technical applications. This bachelor’s thesis aims to analyze the local structure of the metal halide perov skite EAxMA1−xPbI3 and in particular to see how the local structure is affected by the cation composition x. By analyzing how the chemical composition affects the structure of the material at room temperature, new knowledge is obtained, which is of purely scientific interest, but can also be used as a reference for the purpose of optimizing stability and efficiency of the material. The scientific method for these studies involves infrared (IR) spectroscopy and Raman spectroscopy, together with studies of the materials photoluminescence. The reason behind this thesis is the stabilization challenges that currently limit the practical application of perovskites. The well-researched material MAPbI3 exhibits good qualities, but is sensitive to chemical degradation. Introducing EA+ is relevant since it shows potential to stabilize the structure, though it has not yet been studied how the substitution affects the properties of the material. This thesis shows how the cation composition has a direct and measurable impact on the local structure of the metal halide perovskites. The results present useful information that corresponds to relevant literature. The thesis might be useful in the next generation’s technical applications with customized features.
- Mekanokemisk syntes av metall organiska ramverk för katalytiska väteutlåningsreaktioner(2026) Andersson, Oskar; Ivarsson, Lydia; Lam, Elina; Svensson, Emil; Wedding, ElsaMetal-organic frameworks are porous coordination polymers with high specific surface area and flexibility upon functionalisation, which makes them interes ting for heterogeneous catalysis. In this study, metal-organic frameworks were synthesised mechanochemically and subsequently evaluated for their catalytic ac tivity in borrowing hydrogen reaction for N-alkylation of aniline with benzyl alcohol. Mechanochemical synthesis was performed on five metal-organic frameworks, NH2-MIL-88(Fe), NH2-MIL-125(Ti), MIL-100(Fe), Zr-MOF-818, and Cu-MOF-74. They were then characterised using powder diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, and gas adsorption to investigate structure, crystallinity, and thermal stability. The results showed that only NH2-MIL-88(Fe) and NH2-MIL-125(Ti) were successfully synthesized. They were then tested for their activity in borrowing hydrogen reactions, also called hydrogen autotransfer reactions, and the reaction mixtures were subsequently analysed with nuclear magnetic resonance spectroscopy. Both frameworks presented catalytic activity, however NH2-MIL-88(Fe) showed the best result under the investigated reaction conditions. Furthermore, the reaction outcome improved with extended reaction time and the addition of a base. The project concludes that mechanochemical synthesis is one possible met hod for producing metal-organic frameworks, but the method entails restrictions with crystallinity and reproducibility. The results show that these materials possess catalytic activity and therefore be suited for borrowing hydrogen reactions.
- Återvinning av kritiska råmaterial från gruvavfall med hjälp av hydrometallurgiska processer(2026) Nilsson, Wilma; Hägglund, Vera; Albrechtsson, Simon; Islamovic, DinoRecycling of critical materials from mining waste by using hydrometallurgical processes– a study that investigates the potential of organic acids as leaching agents for boron, lithium and copper. During the coming years, the need for critical and strategical elements, such as boron, lithi um and copper, is expected to increase rapidly. From this, it follows that the importance of extracting a larger part of elements from mining waste also heightens. A traditional method for material recovery is through leaching with inorganic acids, which leads to environmentally harmful emissions. If such leaching can be done with organic acids, that do not lead to such emissions, it would be beneficial for both the industry and the environment. The aim of this work is to develop an effective method for the leaching of boron, lithium and copper from mi ning waste using organic acids as leaching agents. The ambition is to achieve equal leaching yields using organic acids as opposed to inorganic, through a process compatible with the in dustry. To achive the aim, leaching of three different mining wastes, containing boron, lithium and copper respectivly, was carried out using organic acids. Leaching efficiency of Na-EDTA, oxalic, acetic and formic acid as leachant was investigated. The impact of acid concentration, temperature, leaching time, solid to liquid ratio and the addition of hydrogen peroxide for these acids were all evaluated. The leaching of boron, lithium and copper, similar or higher leaching yields were obtained with organic acid as with inorganic acid leaching. For boron leaching, a yield of around 100 % was reached in several leaching conditions with oxalic acid during two hours. For lithium leaching, a yield of around 100 % was reached with oxalic acid, but after four hours. For copper, the highest leaching yield achieved was around 45 %, and this was done with Na-EDTA. The advantageous results achieved for boron and lithium leaching provides a good reason to continue exploring the possibility to implement these leaching conditions on an industrial scale. To make a continued scientific work on an industrial scale applicable for copper leaching, a higher leaching yield must be attained.
- The usage of Metal Organic Frameworks for the removal of PFAS from water(2026) Millbom Gustavsson, Svea; Wirzen, Ella; Skoog, Gustav; Sollied, Anton; Lamme, Albin; Edgren, AdamThis project encompases the green synthesis of two Metal Organic Frameworks (MOFs), along with an evaluation of their efficacy to remove PFAS from water. The included MOFs are UiO-66, synthesized in propylene carbonate (PC), and MOF-808, synthesized in water, alongwithperflourooctanoic acid(PFOA),andtriflouroaceticacid(TFA)asthechosenPFAS substances. To enable this, multiple methods of analysis and characterization are used. With the premiss of previously published papers, solvothermal synthetic methods are deve loped. PXRD, TGA and FTIR are utilized as characterization methods along with gas sorp tion, where the BET-theory was used to estimate the apparent surface area of the MOFs. The data from the PXRD and the FTIR are similar to the simulated data for both UiO-66 and MOF-808. However, for UiO-66, the TGA and the apparent surface area show deviations. Simultaneously, the MOFs’affinityforPFASisevaluatedthroughsorbtionexperimentswith prepared stock solutions of PFAS. To study this, a 19F-NMR is used, with which the sorption capacity and kinetics are determined. To evaluate these, both the amount of MOF to PFAS, along with the sorption over different time intervals, are included. Evaluating the PFAS sorption experiments,MOF-808exhibitsthebestaffinityforbothPFOA andTFA,removingapproximately89%and58%respectively.Saturationisreachedwithin10 min. UiO-66 also shows good sorption, though with smaller capacity, removing approxima tely 86% of PFOA and 36% of TFA, with saturation reached within 20 min. However, UiO-66 reaches saturation faster for PFOA. The sorption follows pseudo-second-order kinetics. The roles of the solvents are discussed further with respect to the results, and thus pos sible areas of improvement of the project. Additionally, the reusability of recovered MOF materials is discussed as a potential direction for future studies.