Nanotechnology as a field has the potential to answer some of the major challenges that mankind faces in regards to environmental sustainability, energy generation and health care. Though, solutions to these concerns can not necessarily rely on our current knowhow. Instead, it is reasonable to expect that humanity must adapt and learn to develop new materials and methods to overcome the adversities that we are facing. This master thesis has involved developing novel materials, serving as a small step in the continuous march towards a bright future where this is possible. More specifically, this work sought to combine mesoporous magnesium carbonate with various metal-organic frameworks to utilize the beneficial aspects from each of these constituents. The ambition was that these could be joined to render combined micro-/mesoporous core-shell structures, with high surface areas and many active sites whilst maintaining a good permeability. Numerous different synthesis routes were developed and explored in the pursuit of viable routes to design novel materials with potential future applications within for instance drug delivery, water harvesting from air and gas adsorption. Coreshell structures of the hydrophilic mesoporous magnesium carbonate covered with the hydrophobic zeolitic imidazole framework ZIF-8 was successfully synthesized for the first time, and practical studies demonstrated a dramatically enhanced water stability, which is perceived to have an impact on further research on these materials. ZIF-67 was also combined with mesoporous magnesium carbonate in a similar manner. Further, Mg-MOF-74 was grown directly from mesoporous magnesium carbonate, where the latter acted as a partially self-sacrificing template, with the aim of rendering a porous hierarchical structure with contributions from the micro- and mesoporous ranges. The outcomes of all these syntheses were characterized using several analyzing methods such as scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and nitrogen sorption analysis.

High power impulse magnetron sputtering has shown a lot of promise as a way of depositing photocatalytic thin films of titanium dioxide at low temperatures, however, the films deposited are often amorphous and display uncertain photocatalytic abilities. This thesis explores the deposition and characterization of photocatalytic thin films deposited with high power impulse magnetron sputtering.  Multiple films were deposited with reactive sputtering in both the oxide and metal mode of operations at different temperatures, duty cycles and substrate biases. The crystal structure, microstructure and photocatalytic activity of the samples were then characterized in order to correlate to each other as well as the growth conditions. Crystallinities were determined via a combined use of gracing incidence x-ray diffraction and Raman spectroscopy, microstructures were explored in cross-sectional images taken using scanning electron microscopy and the photocatalytic ability was measured by quantifying the rate constant during degradation of stearic acid while under UV-illumination.  It was found that the crystal structure of the sputtered films was influenced by the deposition mode used: oxide mode depositions yielded an anatase structure while metal mode depositions resulted in rutile or mixed structures. The only crystalline films were formed with substrate heating, the application of bias was found to correlate with the formation of more rutile and the most crystalline films were deposited with a higher duty cycle.  Photocatalytic films were successfully deposited at room temperature, even though they were amorphous. Interestingly, the anatase samples were not found to be the most reactive, instead it was found that the crystal structure only displayed a weak correlation to the reactivity of the films. The findings in this work suggest that the reactivity was also heavily influenced by the surface roughness of the samples as well as their microstructures.

Cement is produced in three main steps: grinding of a mixture of raw materials, sintering of the raw meal to form clinker, and grinding and mixing of clinker, gypsum and additives to make cement. Slag from steel manufacturing can be used to replace some of the raw material, but since slag is a carrier of some unwanted compounds, problems arise. Excess sulphur circulating in the system during clinker production can cause various problems such as clogging. In this report, the circulation of sulphur and other volatile compounds as well as the composition of gaseous and solid materials in the cyclone tower has been studied using old data from 2014 and new measurements. No sulphuric gases were found in the cyclones, so it was concluded that most of the sulphur condenses at the bypass at the inlet to the cyclone closest to the kiln. Condensation is assumed to occur early in the pre-heating tower because of air leaking in. Sulphur balances from 2014 and 2020 showed that usage of slag increases the amount of sulphur that circulates in the system and that the critical amount has been exceeded as of the measurements taken 2020. It is recommended that further measurements are performed, such as qualitative analysis of the solid material to distinguish the different sulphuric compounds, as well as more experiments with varied parameters such as the amount of slag and kiln fuel used.

The Latin American steel making company Ternium S.A. aims to develop and produce a new type of advanced high strength steel (AHSS) in which the main alloying elements are carbon, aluminium, manganese, and silicon. The present work is the first phase of the development project and it involves casting and characterization of four steel compositions with varying amounts of the aforementioned elements. The results revealed that the Mn-content had a large impact on the development of hard phases during solidification. A steel with a Mn-content of 2 %wt. had almost completely transformed to pearlite during cooling, while a steel with a 4 %wt. Mn-content consisted of primarily martensite and retained austenite. Only the impact of the Mn-content is evaluated. The columnar grain size for two of the four steel compositions were in the range of 20-30 mm, which is similar to those observed from continuous casting. This indicate that the heat transfer rate was slow enough to allow these grains to grow. Measurements during casting showed an initial cooling rate of 10-20°C/min at a distance of 10 mm inside the ingot, which is much slower than the surface cooling rate during continuous casting (100-150°C/min). It was assumed that the cooling rate was similar for all castings since the methodology was identical. However, the steel used for cooling rate measurements was not characterized, why a correlation between cooling rate and composition could not be obtained. A heat transfer model was developed to gain further knowledge of the solidification process. As a reference to the heat transfer model, a eutectic Bi-42Sn alloy was cast with temperaturemonitoring using a casting setup identical to that of the steel castings. A similar cooling rate tothe Bi-42Sn reference casting was obtained where the cooling was faster from above of the ingot than below. Thus, the last part of the metal to solidify during the simulation was situated in the lower half of the ingot. This provides a model for testing future steel compositions.

Perovskite solar cells exhibit outstanding device performance and photovoltaic potential in recent ten years. However, the photoactive layer of the majority of perovskite solar cells with outstanding efficiency currently contains toxic lead. Although perovskite solar cells will be encapsulated prior to application to enhance the device's stability and prevent lead leakage, it is still possible for the devices to be broken or exposed to the environment during actual use. Correspondingly, Pb may enter water or soil through rainfall, posing health risks to humans and other creatures. To prepare perovskite solar cell devices with both high performance and low toxicity, current research concentrates primarily on Pb-Sn hybrid perovskite solar cells as Sn is less toxic than Pb from an environmental standpoint. To intuitively compare the lead leakage of Pb-based perovskite solar cells and Pb-Sn hybrid perovskite solar cells, this study simulated the lead leakage scenario under heavy rainfall conditions using self-prepared, good-performance solar cell devices. Our results indicate that Pb-Sn hybrid perovskite solar cells have less lead leakage than Pb-based perovskite solar cells. The lead leakage concentration of Pb-Sn hybrid perovskite solar cells was 36.8% (in the dripping test) and 41.2% (in the soaking test) lower than that of Pb-based perovskite solar cells.

Industries’ interest in nanomaterials is tremendous and catalysis is one of their applications. Catalysts allow reactions to occur under milder conditions, avoiding committing excessive heat or pressure to foster reactions. The discovery of Frustrated Lewis Pairs (FLP) in 2006 led to a new concept of homogeneous catalysis: metal-free acids and bases preventing from forming an Lewis adduct because their bulkiness create an active clamp that is able to cleave dihydrogen and other small molecules at room temperature. Transferring the FLP concept to the “nano”-world which is more relevant for industrial applications, requires well-designed nanoparticles and rationalization of their interaction with ligands aiming at forming a FLP between nanoparticles and ligands. The following project conducted at LCMCP (Laboratoire de Chimie de la Matière Condensée de Paris) under the supervision of Sophie Carenco aimed at studying the insertion of phosphorus in metallic nanoparticles in order to tune their catalytic activity and demonstrate Frustrated-Lewis Pair catalytic behaviours. To that end, copper nanoparticles and bimetallic core-shell nickel-cobalt nanoparticles were synthesized in colloidal solution. The phosphidation of both nanoparticles was investigated with trioctylphosphine (TOP) as the phosphorous source. Nanoparticles were characterized by X-Ray Diffraction, Transmission Electron Microscopy and X-ray Photoelectron Spectroscopy. Starting from the failure to reproduce a published procedure of copper phosphide nanoparticles synthesis, conditions of the reaction and the washing procedure were successively improved aiming the obtention of copper phosphide nanoparticles. The one-pot synthesis with hot-injection of TOP at the second step (320°C, 1h), allowed to isolate copper phosphide nanoparticles but a longer reaction time did not result in enhanced phosphorus doping. Further work would need to examine the reproducibility problems faced and investigate harsher reaction conditions (eg. higher temperature). Cu3P nanoparticles would be interesting to test as catalysts for hydrosilylation of benzaldehyde or CO2, a model reaction for CO2 hydrogenation. The synthesis of core-shell nickel-cobalt nanoparticles has been previously rationalized by Sophie Carenco’s team. Phosphidation was attempted from this optimized procedure. We started with harsh conditions (> 250°C, > 1h30) which caused reconstruction of the nanoparticles after leaching of the cobalt shell. In such conditions, the core-shell structure is not retained and a NiCoP alloy is obtained. Milder conditions allowed to retain the structure but further studies are required to characterize and locate the phosphorus insertion in the core-shell nanoparticles. NiCoP alloy and phosphidized core-shell Ni@Co will be of great interest to apply in catalysis for water splitting and hydrogenation of nitriles, respectively.

Tuberculosis (TB) is an airborne disease caused by Mycobacterium tuberculosis, with an incidence in a quarter of the world population. Despite the scientific and technological advances, an effective diagnostic method has not yet been found that allows an early diagnosis and, also, to detect the strain present in the patient. The combination of nanotechnology with molecular diagnostics has shown promising advances offering new possibilities, such as the development of nanoflares.  Nanoflares represent a new class of molecular probes, composed of gold nanoparticles functionalized with a recognition sequence that can be amplified by rolling circle amplification (RCA) technique, producing a fluorescence signal.  This thesis focuses in the synthesis of gold nanoparticles, with different coatings and sizes, as well as their subsequent application in the preparation and optimization of nanoflares for the genotyping of synthetic M. tuberculosis targets using RCA technique. The different preparations of nanoflares have an impact in the assay sensitivity, showing two times increase in sensitivity for citrate-coated nanoparticles with respect to those coated with PEG. Furthermore, it was observed that the sensitivity is directly related to the synthesized particle size.  Sensitivity is also affected by the application of a purification post-treatment of the synthesis product. This post-treatment reduces the sensitivity of nanoflares by up to 37% but, by contrast, extends its useful life.  The results obtained are shown as a proof of concept for a future cost-effective, rapid and robust in situ diagnostic method that identifies the strain of tuberculosis present in the patient.

Den additiva tillverkningsindustrin associeras ofta med en hållbar hushållning av resurser. Trots detta har denna industriavfall med stor potential till vidare användning. Detta kandidatexamensarbete undersöker möjligheten att använda Polyamid 12 (PA12) avfall från selektiv lasersintring (SLS) i formen av filament till en annan additiv tillverkningsmetod, friformsframställning. Avfall från olika delar av SLS-processen försågs av life science företaget Cytiva. Olika blandningar av avfallen extruderades till filament. Innan extrudering undersöktes innehåll samt de termiska egenskaperna hos avfallet med hjälp av differentiell skanningskalometri (DSC), termogravimetrisk analys och fourier transform infraröd spektroskopi. Filamenten analyserades med dragprovning, DSC och svepelektronmikroskopi. Rent obearbetat PA12 pulver och ett kommersiellt PA12 filament användes som referenser vid jämförelse. Blandningarna innehållande avfall från SLS-printerns automatiska rengöringsprocess var kontaminerade med glaspartiklar och blev därför spröda och erhöll en skrovlig yta. Dessa filament gick inte att 3D-printa eftersom glaspartiklar ansamlades i munstycket av printern. Flera filament fick en ojäm och liten diameter och kunde därför inte användas i 3D-printern. Ojämn och liten diameter blev resultatet av bekymmer med sensorn som mäter diametern av filamenten. Dessa filament gjordes av granulerade utskrivna prototyper, pulver nära utskrivna delar och silat pulver långt ifrån de utskrivna delarna. Filament gjorda på blandningar innehållande avfall från dammsugaren som används för att rengöra SLS-printern kunde med framgång skrivas ut i 3D-printern. Dessa filament hade en jämn diameter och innehöll inga större kontamineringar. Det är därför genomförbart att tillverka filament av avfall från alla delar av SLS-processen även om inte alla filament kunde 3D-printas. / Additive manufacturing is often associated with sustainable use of resources. However, this industry still has material waste with great potential for further use. This bachelor thesis examines the opportunity of using Polyamide 12 (PA12) waste from Selective laser sintering (SLS) in the form of filaments for another additive manufacturing method, fused filament fabrication. Waste from different parts of the SLS process were provided from the life science company Cytiva. Several blends of the waste were made into filaments. Prior extrusion, the thermal properties and content of the waste were examined with differential scanning calorimetry (DSC), thermogravimetric analysis and fourier transform infrared spectroscopy. The filaments were analyzed by tensile testing, DSC and scanning electron microscopy. Pure virgin powder of PA12 and a commercial PA12 filament were used as a reference for comparison. The blends containing waste from the SLS printer’s automatic blasting was contaminated with glass beads which resulted in brittle filaments with a rough surface. These filaments were not possible to 3D print with due to accumulation of glass beads in the nozzle of the printer. Several filaments got an uneven and small diameter and could therefore not be 3D printed with. The small and uneven diameter was a result of issues with the sensor measuring the diameter. This includes filaments made of granulated printed prototypes, powder close to the printed parts and sieved powder further away from printed parts. The filaments made of blends including waste from the vacuum cleaner used to clean the SLS printer could successfully be used in printing. These filaments had an even diameter and did not contain any larger contaminations. It is therefore possible to make filaments from waste from all parts of the SLS process although not all filaments could be 3D printed.

When slow wear mechanisms are studied it is important to examine slower processes, such as diffusion. Such processes can have a significant impact over time and can cause other phases to form, which can have a large effect on the wear. This thesis has investigated the diffusion that is believed to take place between brass and cemented carbide tools. This was done to further the understanding of the slow atomic wear which if properly understood, could lead to solutions that would increase the lifetime of the tools. The diffusion pairs were made from a tribological contact and then heat treated to speed up the diffusion process. Different temperatures and times were tested, from 400 °C for 3 h to 700 °C for 24 h. The samples were analysed with SEM and EDS both before and after the heat treatment, to see if diffusion had taken place. However, because of many unexpected processes and reactions the analysis could not confirm that diffusion had taken place. The transportation of Cu at the higher temperatures was much faster than expected, and in some samples, Cu could not be detected after the heating. Since the surface was so mobile, the slower diffusion process did not have time to take place. Many improvements for future experiments are suggested to be able to observe the diffusion, such as depositing a thin film or adding more work material.

The market is in great need of more environmentally friendly alternatives to fossil-based composite materials to obtain a more sustainable future. Lignin is the second most common biopolymer and is a byproduct in the pulping and paper industry. Fractionation of lignin has made it possible to receive lignin with narrow dispersity and low molecular weight, which is suitable for further applications. Modification of lignin structure yields new reactive sites that can be tailored for specific needs. Because of the aromatic structure of lignin, it is a promising renewable resource for production of thermosets. In this project Kraft lignin is sequentially solvent-fractionated and modified in an allylation process with allyl chloride. The allylated lignin is reacted with a cross-linking agent and used to impregnate carbon fibre mats. The resin-coated material is then cured at 125 oC to achieve a composite material. The project also encompasses characterization of the chemical structure of lignin in the different fractions. The morphology and adhesive properties of the lignin as well as the carbon fibres and the composite material was investigated. Although the production of composite material from lignin and carbon fibres were accomplished, bubble formation in the resin was a problem for all composite samples that were prepared, whether it was during solvent evaporation or during curing. By performing the addition of resin to carbon fibre mats in multiple steps, where pressure is added after the first applied layer, it is suggested that complete adhesion to the carbon fibre can be achieved, whilst maintaining adequate resin to carbon fibre ratio. / Marknaden är i stort behov av mer miljövänliga alternativ till fossilbaserade kompositmaterial för att kunna erhålla en mer hållbar framtid. Lignin är den näst vanligaste aromatiska biopolymeren och framställs som en biprodukt i pappersindustrin. Fraktionering av lignin har gjort det möjligt att erhålla lignin med låg dispersitet och molekylvikt vilket är lämpligt för vidare applikationer. Modifiering av lignins struktur ger upphov till nya reaktiva grupper som kan anpassas för ens behov. Den aromatiska strukturen som lignin besitter resulterar i en lovande förnybar resurs för produktion av härdplast. I detta projekt är Kraft lignin sekventiellt fraktionerat med lösningsmedel och modifierat med hjälp av en allyleringsprocess i närvaro av allylklorid. Det allylerade ligninet reagerar med en tvärbindare och används vidare för att impregnera kolfiber. De impregnerade kolfibermattorna härdades i ugn vid 125 oC för att erhålla kompositmaterial. Projektet omfattar även karaktärisering av den kemiska strukturen i lignin från de olika fraktionerna. Morfologin och vidhäftningsförmåga av lignin, kolfiber och likaså kompositmaterialet undersöktes. Ett kompositmaterial bestående av kolfiber och lignin erhölls med framgång under projektets gång, dock var bubbelbildning ett stort problem under förångningen av lösningsmedel och även under härdningsprocessen. Addition av harts till kolfibermattorna i flera steg, där tryck är adderat efter det första lagret har blivit applicerat, anses vara en lovande metod för att en hög vidhäftningsgrad ska kunna erhållas. Detta medan ett adekvat förhållande mellan harts och kolfiber upprätthålls.