In nanoparticle research it is common to perform optical measurements on particle films during deposition, to help understand the growth process. GranFilm is a software under development which can calculate the optical properties of an array of truncated nanoparticles supported on a substrate. The theory behind these calculations is based on the work of Bedeaux and Vlieger. One feature which was missing from the software until now was the ability to do such simulations on the case of truncated spheroidal nanoparticles with an arbitrary number of coatings of different materials. In the beginning of this work, the equations needed to perform these simulations are derived, and then reduced to previously derived special cases for verification. The new equations are then implemented into GranFilm, and the new code is put through numerical tests. Finally, the new functionality is tested with the help of experimental data from an oxidation process of a silver nanoparticle film. The qualitative evolution of the optical properties of the film is reproduced quite successfully, but some issues remain.

With the prospect of producing superhydrophobic and mechanically stable biomimetic surfaces, the water repellent properties of springtail cuticles are investigated quantitatively. The analysis is based on apparent contact angle measurements on nine springtail species and SEM and AFM images of their cuticles. It is argued that water exists in a metastable Cassie-Baxter state on the cuticle and that three-phase line tension of the order of 10^-8 J/m contributes to high apparent contact angles. A model is developed to assess the significance of a recently reported re-entrant geometry of the cuticle granules and to study the resistance of the cuticle against wetting. The model estimates that springtails resist wetting under hydrostatic pressures up to 10^4 - 10^5 Pa, and that re-entrant granule profiles increase the wetting resistance by 50 - 400%. To explain the low contact angle hysteresis observed on the cuticles, new equations are proposed to include the effect of three-phase line tension. Again, a line tension magnitude of the order of 10^-8 J/m can account for the experimental findings. This work indicates that the sub-micron size scale of the springtail cuticle granules provides an elegant approach for achieving water repellent and mechanically stable surfaces. Two springtail species are singled out as especially promising for biomimetic applications.

This project aims at the fabrication of a rough polydimethylsiloxane(PDMS) surface with patterned smooth areas. The idea is that such a surface will allow for water capturing on the smooth areas of the surface. The applications for this kind of surface are many, but especially the prospects of a surface able to trap droplets of cells in suspension by simply dipping the surface into the suspension is intriguing.From a previous project[1], and another student’s master’s thesis[2], the use of an etched copper surface seemed promising for the fabrication of a rough mold. This was abandoned after sandpaper turned out to be an even better mold, giving superhydrophobic PDMS(162, 33 ± 1, 40degrees).The negative photoresist SU-8 5 was used to pattern the sandpaper with small, circular features on the P1000 sandpaper(400μm and 1mm in diameter). The PDMS replica from this mold was a rough surface with smooth wells. This was not able to capture water droplets effectively, partly because air bubbles were trapped in the wells during the immersion in water. To avoid this, another mold was procured by the silanization of the previously made PDMS surface. The PDMS replica of the silanized PDMS had smooth pillars instead of wells, and did not succeed in trapping water droplets either. In fact, the smooth wells seemed to better at capturing the water.This project has succeeded in producing high enough roughness on PDMS to alter the contact angle with water by ∼ 61 degrees to a contact angle exceeding the lower limit for superhydrophobic surfaces by ∼ 12 degrees. The use of a sandpaper mold has proven to is simple, inexpensive and effective at producing PDMS with high contact angles.

In the present study, a process for fabricating GaAs nanowire/graphene hybrid devices using electron beam lithography processing techniques is presented and demonstrated. Fabricated devices were investigated electronically by measuring emph{I-V} characteristics under a variable gate voltage.Fabrication processes for both exfoliated and CVD-grown graphene were developed. For exfoliated graphene the outlined process is unsuccessful, as the graphene flakes were found to crumble and fall off during the first processing step following transfer. It is thus concluded that exfoliated graphene flakes are too delicate to perform any significant processing after graphene transfer.The fabrication process was successfully demonstrated in fabrication of devices with CVD-grown graphene. However, nanowires in these devices were seen to undergo significant corrosion during the process, which is credited to the water exposure associated with graphene transfer. This was found to be an especially prominent issue for contacted nanowires, where the metal contact is believed to facilitate galvanic corrosion. I-V characteristics and gate voltage dependence were measured for GaAs nanowire/graphene hybrid devices made with CVD-grown graphene. Large variations in the I-V behavior and gate voltage dependence was observed. This is credited to corrosion in the nanowires, which is thought to result in uncharacteristic behavior for metal-GaAs contacts. There are also indications that several devices are shortened by graphene. The electronic investigations are therefore found to be inconclusive in respect to the electronic properties of the graphene/GaAs nanowire junction. It is concluded that further developments in the fabrication process are needed to achieve GaAs nanowire/graphene hybrid devices suitable for detailed analysis.

<p>The aim with this essay is to find out what the expected changes in the subject physics will lead to for teachers and their pupils in “gymnasiet”. The new fields we have chosen to focus on are electronic structure of condensed matter, nanotechnology and material physics. By studying earlier used curricula and textbooks, we illustrate what teachers may have come into contact with in their teaching careers. The main focus lies on what teachers claim to know about the fields mentioned above and if there is a need for further education. Our results indicate that teachers in general feel insecure about their knowledge of these fields and that further education is desirable. The studied group of teachers also have wishes on how to form possible further education.</p> / <p>Syftet med arbetet är att undersöka vad de väntade förändringarna av fysikämnet kommer att innebära för fysiklärare och elever i den svenska gymnasieskolan. De nya områden vi har valt att fokusera på är den kondenserade materiens elektronstruktur, nanoteknologi samt materialfysik. Genom studier av äldre kursplaner och läroböcker ger vi en bild av vad lärarna kan ha stött på tidigare i deras fysikundervisning. Tyngdpunkten ligger i vad lärarna anser sig kunna inom de ovan nämnda områdena samt om det föreligger något fortbildningsbehov. Våra resultat tyder på att lärarna i allmänhet känner en stor osäkerhet inför dessa nya områden och att fortbildning är önskvärt. De lämnar även önskemål om utformning av en eventuell fortbildning.</p>

The aim with this essay is to find out what the expected changes in the subject physics will lead to for teachers and their pupils in “gymnasiet”. The new fields we have chosen to focus on are electronic structure of condensed matter, nanotechnology and material physics. By studying earlier used curricula and textbooks, we illustrate what teachers may have come into contact with in their teaching careers. The main focus lies on what teachers claim to know about the fields mentioned above and if there is a need for further education. Our results indicate that teachers in general feel insecure about their knowledge of these fields and that further education is desirable. The studied group of teachers also have wishes on how to form possible further education. / Syftet med arbetet är att undersöka vad de väntade förändringarna av fysikämnet kommer att innebära för fysiklärare och elever i den svenska gymnasieskolan. De nya områden vi har valt att fokusera på är den kondenserade materiens elektronstruktur, nanoteknologi samt materialfysik. Genom studier av äldre kursplaner och läroböcker ger vi en bild av vad lärarna kan ha stött på tidigare i deras fysikundervisning. Tyngdpunkten ligger i vad lärarna anser sig kunna inom de ovan nämnda områdena samt om det föreligger något fortbildningsbehov. Våra resultat tyder på att lärarna i allmänhet känner en stor osäkerhet inför dessa nya områden och att fortbildning är önskvärt. De lämnar även önskemål om utformning av en eventuell fortbildning.

In the industry of today, materials which can adsorb and hold large amounts of water are playing an important role. Here, the free and bound water carrying capacity of an amorphous magnesium carbonate is investigated. It is also determined how these parameters depend on the relative humidity of the surrounding environment. To do this, the technique of dielectric spectroscopy is employed. Along with the water binding properties, the concentration of charge carriers and the diffusion coefficient was determined. A smaller part of around 10-30 % of the water adsorbed was shown to behave as free water in the material. The concentration of charge carriers was calculated to be in an order of magnitude of 1018-1022 m-3 for the higher relative humidity environments. The diffusion coefficient was shown to be about 5*10-9 m2/s for the adsorption spectrum. This value is in good agreement with the value for OH- ions in water.

Nano materials can today be found in a wide range of consumer products and the number of new products on the market is expected to inrease. In the shadow of hope for nano materilas potential in various applications, low awareness of its health and environmental risks is hiding. Furthermore, the knowledge about people´s risk perception of nano materials is limited. Parallel to the situation described above, the scholls meet the challenge of incrasing the scientific literacy. To achieve this goal, skills in argumentation in science studies has been emphasized and the concept of socio-scientific issues has been emerged. Using focus groups as a method, this study aimed first, to explore young engineering student´s risk perception of nano materials, and secont to analyze the extent to which they apply scientific konwledge to argue about nano materials. The material from the focus group interviews was analyzed with respect to both content and interaction. To analyze the content, a thematic classification of the material was made. The interactive and communicative forms were highlighted by an analysis of arguments according to the SEE-SEP-model. Seven themes were indentified from the focus group material. It was also assumed that 55 percent of the participants´arguments were based on values, 25 percent on konwledge and 20 percent on personal experiences. Despite the absence of specific knowledge, the young engineering students have the ability to conduct a complex argumentation about nano materials where they involve the paradox; new opportunities, inresolved risks. Their risk perception is not primarily based on knowledge but on emotional expressions such as fascination, hope, resignation and fear. / Nanomaterial återfinns idag i ett brett spektrum av konsumentprodukter och antalet nya produkter förväntas öka på marknaden. I skuggan av förhoppningar om nanomaterialens potential i allehanda tillämpningar döljer sig bristfälliga kunskaper om dess hälso- och miljörisker. Vidare är kunskapen om människors riskpercetion an nanometrial begränsad. Parallellt med den ovan beskrivna situationen står skolan inför utmaningen att öka den naturvetenskapliga allmänbildningen. För att uppnå målet har kompetens inom argumentation i de naturorienterande ämnene betonats och begreppet sociovetenskapliga dilemman vuxit fram. Med fokusgrupper dom metod har studien syftat dels till att undersöka unga teknikstuderandes riskperceetpion av nanomaterial, dels till att analysera i vilken utsträckning de tillämpar vetenskapliga kunskaper för att argumentera om nanomaterial. Materialet från fokusgruppsintervjuerna analyserades med avseende på både innehåll och interaktion. För att analysera innehållet gjordes en tematisk indelning av materialet. De interaktiva och kommunikativa formerna belystes genom en argumentationsanalys enligt SEE-SEP-modellen. Sju teman identifierades ur fokusgruppmaterialet. Vidare utgick 55 % av deltagarnas argument från värderingar. därefter kom kunskap med 25 % och sist personliga erfarenheter med 20 %. Trots avsaknad av specifik kunskap, har unga teknikstuderande förmågan att föra en komplex argumentation om nanomaterial där de berör pradoxen; nya möjligheter, outredda risker. Deras riskperception baseras inte främst på kunskaper utan på emotionella uttryck så som fascination, hopp,uppgivenhet och rädsla.

Lead Halide Perovskite is emerging quickly as a promising material for the future solar cellsthanks to their inherent good optoelectrical properties along with their cheap and facile fabri-cation. However, their main drawback before commercialization is their weak stability. In thiswork, a novel carbon-coated perovskite quantum dot has been synthesized, and is to the extentof our knowledge, for the first time. The coated perovskite quantum dots show a remarkable in-creased stability under different conditions while in solution. Their photoluminescence intensityalso increased as time went on, exceeding that of the uncoated perovskite quantum dots aftera few weeks. These coated perovskite quantum dots, while not fully characterized and thusnot fully understood show a promising way on how to combat the low stability in perovskites.Further, Copper/Copper(I)Iodide core/shell nanowires were synthesized as a transparent inte-grated hole transport layer/electrode for solar cells. While limited due to the low controlledfabrication process used, they providing a solid base for further research on the material to beused in solar cells. / Bly-halid perovskite har snabbt utvecklats och visar sig vara ett lovande material till framti-dens solceller tack vare dess optoelektriska egenskaper samt dess billiga och lätta tillverkn-ingsprocess. Dock, så brister materialet på grund av dess dåliga stabilitet innan de kan kommer-sialieras fullt ut. I detta projekt har kol-överdragen perovskite kvantprickar framställts, och ärtill den omfattning vi besitter, för första gången. De coatade perovskite kvantprickarna visade enförvånadsvärd stabilitet under olika tillstånd, och även en ökning i dess photoluminescens efternågra veckor. Dessa kvantprickar, dock ej ännu fullt förstådda och mer karaktärisering krävs, ärett lovande alternativ till att lösa perovskitens låga stabilitet. Vidare har koppar/koppar(I)jodidcore/shell nanotrådar tillverkats som en transparent integrerar håltransport material/elektrodför solceller med goda egenskaper. Trotts sin begränsning i den framställningsprocess som an-vändes ger dem en lovande bas för framtida forskning på materialet.

The chemical bond – a corner stone in science and a prerequisite for life – is the focus of this thesis. Fundamental and applied aspects of chemical bonding are covered including the development of new computational methods for the characterization and rationalization of chemical interactions. The thesis also covers the study of corrosion of copper-based materials. The latter is motivated by the proposed use of copper as encapsulating material for spent nuclear fuel in Sweden. In close collaboration with experimental groups, state-of-the-art computational methods were employed for the study of chemistry at the atomic scale. First, oxidation of nanoparticulate copper was examined in anoxic aqueous media in order to better understand the copper-water thermodynamics in relation to the corrosion of copper material under oxygen free conditions. With a similar ambition, the water-cuprite interface was investigated with regards to its chemical composition and reactivity. This was compared to the behavior of methanol and hydrogen sulfide at the cuprite surface. An overall ambition during the development of computational methods for the analysis of chemical bonding was to bridge the gap between molecular and materials chemistry. Theory and results are thus presented and applied in both a molecular and a solid-state framework. A new property, the local electron attachment energy, for the characterization of a compound’s local electrophilicity was introduced. Together with the surface electrostatic potential, the new property predicts and rationalizes regioselectivity and trends of molecular reactions, and interactions on metal and oxide nanoparticles and extended surfaces. Detailed atomistic understanding of chemical processes is a prerequisite for the efficient development of chemistry. We therefore envisage that the results of this thesis will find widespread use in areas such as heterogeneous catalysis, drug discovery, and nanotechnology. / Den kemiska bindningen – en hörnsten inom naturvetenskapen och oumbärlig för allt liv – är det centrala temat i den här avhandlingen. Både grundläggande och tillämpade aspekter behandlas. Detta inkluderar utvecklingen av nya beräkningsmetoder för förståelse och karaktärisering av kemiska interaktioner. Dessutom behandlas korrosion av kopparbaserade material. Det sistnämnda är motiverat av förslaget att använda koppar som inkapslingsmaterial för hanteringen av kärnavfall i Sverige. Kvantkemiska beräkningsmetoder enligt state-of-the-art har använts för att studera kemi på atomnivå, detta i nära sammabete med experimentella grupper. Initialt studerades oxidation av kopparnanopartiklar under syrgasfria och vattenrika förhållanden. Detta för att bättre kartlägga koppar-vattensystemets termodynamik. Av samma orsak detaljstuderades även gränsskiktet mellan vatten och kuprit med fokus på dess kemiska sammansättning och reaktivitet. Resultaten har jämförts med metanols och vätesulfids kemiska beteende på ytan av kuprit. En övergripande målsättningen under arbetet med att utveckla nya beräkningsbaserade analysverktyg för kemiska bindningar har varit att överbrygga gapet mellan molekylär- och materialkemi. Därför presenteras teoretiska aspekter samt tillämpningar från både ett molekylärt samt ett fast-fas perspektiv. En ny deskriptor för karaktärisering av föreningars lokala elektrofilicitet har introducerats – den lokala elektronadditionsenergin. Tillsammans med den elektrostatiska potentialen uppvisar den nya deskriptorn förmåga att förutsäga samt förklara regioselektivitet och trender för molekylära reaktioner, och för interaktioner på metal- och oxidbaserade nanopartiklar och ytor. En detaljerad förståelse av kemiska processer på atomnivå är en nödvändighet för ett effektivt utvecklande av kemivetenskapen. Vi förutspår därför att resultaten från den här avhandlingen kommer att få omfattande användning inom områden som heterogen katalys, läkemedelsdesign och nanoteknologi. / <p>QC 20170829</p>