Microbial colonization on the surface of silicone rubber high voltage outdoor insulators often results in the formation of highly hydrated biofilm that influence the surface properties, such as surface hydrophobicity. The loss of hydrophobicity might lead to dry band formation, and, in the worst cases, flashover and failure of the insulator. In this work, the biocidal effects of various antimicrobial compounds in silicone rubber materials were determined. These materials were evaluated according to an ISO standard for the antimicrobial activity against the growth of aggressive fungal strains, and microorganisms that have been found colonizing the surfaces of outdoor insulators in several areas in the world. Several compounds suppressed microbial growth on the surfaces of the materials without compromising the material properties of the silicone rubber. A commercial biocide and thymol were very effective against fungal growth, and sodium benzoate could suppress the fungal growth to some extent. Thymol could also inhibit algal growth. However, methods for preservation of the antimicrobial agents in the bulk of the material need to be further developed to prevent the loss of the compounds during manufacturing. Biofilm formation affected the surface hydrophobicity and complete removal of the biofilm was not achieved through cleaning. Surface analysis confirmed that traces of microorganisms were still present after cleaning. Further, surface modification of the silicone rubber was carried out to study how the texture and roughness of the surface affect biofilm formation. Silicone rubber surfaces with regular geometrical patterns were evaluated to determine the influence of the surface texture on the extent of microbial growth in comparison with plane silicone rubber surfaces. Silicone rubber nanocomposite surfaces, prepared using a spray-deposition method that applied hydrophilic and hydrophobic nanoparticles to obtain hierarchical structures, were studied to determine the effects of the surface roughness and improved hydrophobicity on the microbial attachment. Microenvironment chambers were used for the determination of microbial growth on different modified surfaces under conditions that mimic those of the insulators in their outdoor environments. Different parts of the insulators were represented by placing the samples vertically and inclined. The microbial growth on the surfaces of the textured samples was evenly distributed throughout the surfaces because of the uniform distribution of the water between the gaps of the regular structures on the surfaces. Microbial growth was not observed on the inclined and vertical nanocomposite surfaces due to the higher surface roughness and improved surface hydrophobicity, whereas non-coated samples were colonized by microorganisms. / <p>QC 20151002</p>

As fachadas das edificações, ao longo de sua vida útil, sofrem degradação devido a ataques de agentes químicos e à deposição de partículas na sua superfície. Como consequências, há perdas no desempenho de seus materiais e a desfiguração estética das fachadas por meio de manchas, implicando em ações de reparo que envolvem custos elevados. Os produtos atualmente disponíveis no mercado brasileiro com objetivo de evitar o manchamento de fachadas têm baixa eficiência, sendo que os principais deles adotam a técnica do pós-tratamento com hidrofugantes, os quais geralmente alteram a coloração do substrato e podem ser a origem de novas patologias. Usufruindo de novas tecnologias, o dióxido de titânio (TiO2) apresenta-se como material nanométrico amplamente estudado na área científica, sendo potencialmente utilizado como fotocalisador. O presente trabalho verificou a possibilidade de obtenção de superfícies autolimpantes a partir da adição de TiO2 em revestimentos de argamassa branca. Estas, a partir de propriedades fotocatalíticas do TiO2 podem ser tornar autolimpantes sob ação da radiação solar (UV) e da chuva. Foram confeccionadas argamassas de traço 1:2 e 1:3, com adições de 0%, 5% e 10% de TiO2 em relação à massa de cimento, com consistência fixa. As amostras foram aspergidas com diferentes agentes manchantes: azul de metileno, particulado de poluição, produto de corrosão, pichação; e sem manchamento (referência). Após, estas amostras foram expostas nas condições ambientais da cidade de Porto Alegre. Ao longo de 84 dias, foram realizadas leituras com espectrofotômetro portátil para avaliar o efeito autolimpante. Também foram verificadas as propriedades físico-mecânicas das argamassas. Os resultados apontaram que argamassas com adição de TiO2 necessitaram maior quantidade de água, apresentaram maior densidade no estado fresco e menor teor de ar incorporado. Ainda, a resistência à compressão foi elevada para o traço mais rico (1:2) e mantida constante para o traço pobre (1:3). Além disso, se mostraram mais claras/brancas quanto maior a porcentagem de adição. O efeito autolimpante pode ser percebido mais facilmente na mancha de azul de metileno, porém, a limpeza ocorreu tanto em argamassas com adição de TiO2, quanto em argamassas sem a adição. Em manchas que geraram uma película sobre a placa, o efeito autolimpante foi dificultado. / The facades of buildings, during their lifespan, suffer degradation due to attacks of chemical agents and due to deposition of particles on their surface. As consequences, there are losses on the performance of their materials and aesthetics disfiguration of the facades by stains, implying repairing actions involving high costs. The products available nowadays on the brasilian market with the purpose to avoid the staining of the facades have low efficiency, and the main products between them adopt the technique of post-treatment with hydrophobing, which generally modify the colour of the substrate and which can originate new pathologies. Taking advantage of new technologies, the titanium dioxide (TiO2) appears as a nanometric material widely studied in the scientific area, being pottentialy used as photocatalyser. The present work has verified the possibility of obtention of self-cleaning surfaces after addition of TiO2 in white mortar coverings. Those, from photocatalyser properties of the TiO2 can become self-cleaning under the action of solar radiation (UV) and rain. There were prepared mortars of trace 1:2 and 1:3, with additions of 0%, 5% and 10% of TiO2 in relation of the cement weight, with steady consistency. The samples were sprinkled with different staining agents: methylene blue, pollution particulates, corrosion product, graffiti; and without stains (reference). After that, these samples were exposed to the ambiental conditions of the city of Porto Alegre. Through 84 days, scannings were made with portable spectrophotometer to evaluate the self-cleaning effect. The physicalmechanical properties of the mortars were also verified. The results point out that mortars with addition of TiO2 required a bigger amount of water, they presented bigger density in the fresh state and smaller contents of incorporated air. Besides, the compression resistance was high to the richest trace (1:2) and remained constant to the poor trace (1:3). Moreover, they have showed themselves more clear/white as bigger was the percentage of addition. The self-cleaning effect can be more easily noticed on the methylene blue stain, however, the cleaning occurred both in mortars with addition of TiO2 and in mortars without the addition. In stains which generate a film above the plate, the self-cleaning effect was hampered.

As fachadas das edificações, ao longo de sua vida útil, sofrem degradação devido a ataques de agentes químicos e à deposição de partículas na sua superfície. Como consequências, há perdas no desempenho de seus materiais e a desfiguração estética das fachadas por meio de manchas, implicando em ações de reparo que envolvem custos elevados. Os produtos atualmente disponíveis no mercado brasileiro com objetivo de evitar o manchamento de fachadas têm baixa eficiência, sendo que os principais deles adotam a técnica do pós-tratamento com hidrofugantes, os quais geralmente alteram a coloração do substrato e podem ser a origem de novas patologias. Usufruindo de novas tecnologias, o dióxido de titânio (TiO2) apresenta-se como material nanométrico amplamente estudado na área científica, sendo potencialmente utilizado como fotocalisador. O presente trabalho verificou a possibilidade de obtenção de superfícies autolimpantes a partir da adição de TiO2 em revestimentos de argamassa branca. Estas, a partir de propriedades fotocatalíticas do TiO2 podem ser tornar autolimpantes sob ação da radiação solar (UV) e da chuva. Foram confeccionadas argamassas de traço 1:2 e 1:3, com adições de 0%, 5% e 10% de TiO2 em relação à massa de cimento, com consistência fixa. As amostras foram aspergidas com diferentes agentes manchantes: azul de metileno, particulado de poluição, produto de corrosão, pichação; e sem manchamento (referência). Após, estas amostras foram expostas nas condições ambientais da cidade de Porto Alegre. Ao longo de 84 dias, foram realizadas leituras com espectrofotômetro portátil para avaliar o efeito autolimpante. Também foram verificadas as propriedades físico-mecânicas das argamassas. Os resultados apontaram que argamassas com adição de TiO2 necessitaram maior quantidade de água, apresentaram maior densidade no estado fresco e menor teor de ar incorporado. Ainda, a resistência à compressão foi elevada para o traço mais rico (1:2) e mantida constante para o traço pobre (1:3). Além disso, se mostraram mais claras/brancas quanto maior a porcentagem de adição. O efeito autolimpante pode ser percebido mais facilmente na mancha de azul de metileno, porém, a limpeza ocorreu tanto em argamassas com adição de TiO2, quanto em argamassas sem a adição. Em manchas que geraram uma película sobre a placa, o efeito autolimpante foi dificultado. / The facades of buildings, during their lifespan, suffer degradation due to attacks of chemical agents and due to deposition of particles on their surface. As consequences, there are losses on the performance of their materials and aesthetics disfiguration of the facades by stains, implying repairing actions involving high costs. The products available nowadays on the brasilian market with the purpose to avoid the staining of the facades have low efficiency, and the main products between them adopt the technique of post-treatment with hydrophobing, which generally modify the colour of the substrate and which can originate new pathologies. Taking advantage of new technologies, the titanium dioxide (TiO2) appears as a nanometric material widely studied in the scientific area, being pottentialy used as photocatalyser. The present work has verified the possibility of obtention of self-cleaning surfaces after addition of TiO2 in white mortar coverings. Those, from photocatalyser properties of the TiO2 can become self-cleaning under the action of solar radiation (UV) and rain. There were prepared mortars of trace 1:2 and 1:3, with additions of 0%, 5% and 10% of TiO2 in relation of the cement weight, with steady consistency. The samples were sprinkled with different staining agents: methylene blue, pollution particulates, corrosion product, graffiti; and without stains (reference). After that, these samples were exposed to the ambiental conditions of the city of Porto Alegre. Through 84 days, scannings were made with portable spectrophotometer to evaluate the self-cleaning effect. The physicalmechanical properties of the mortars were also verified. The results point out that mortars with addition of TiO2 required a bigger amount of water, they presented bigger density in the fresh state and smaller contents of incorporated air. Besides, the compression resistance was high to the richest trace (1:2) and remained constant to the poor trace (1:3). Moreover, they have showed themselves more clear/white as bigger was the percentage of addition. The self-cleaning effect can be more easily noticed on the methylene blue stain, however, the cleaning occurred both in mortars with addition of TiO2 and in mortars without the addition. In stains which generate a film above the plate, the self-cleaning effect was hampered.

Ao longo do tempo, os revestimentos de fachada permanecem expostos a diversos agentes de degradação, sejam eles associados aos próprios materiais empregados ou a fatores externos. Tal exposição implica em manchas formadas a partir da deposição de partículas poluentes na superfície dos revestimentos, elevando seus custos para limpeza e manutenção. Uma vez que permanecem expostas à radiação solar, as fachadas se mostram atraentes ao uso de materiais fotocatalíticos, os quais catalizam a mineralização de agentes poluentes, transformando-os em produtos inócuos. A adição de dióxido de titânio (TiO2) a argamassas e concretos de cimento branco desenvolve superfícies autolimpantes, reduzindo a formação de manchas e mantendo sua coloração original ao longo do tempo. No entanto, a eficiência e a economia no uso de materiais fotocatalíticos em aplicações reais é fortemente afetada pela disponibilidade da radiação ultravioleta adequada para ativá-los. Portanto, o presente trabalho busca avaliar a capacidade autolimpante de argamassas e coberturas fotocatalíticas de TiO2 expostas a diferentes configurações de posicionamento no microclima urbano da cidade de Porto Alegre. Para isto, foram confeccionadas amostras de argamassa e coberturas de pasta ou argamassa contendo diferentes teores de TiO2, as quais foram manchadas com Rodamina B e lodo de cinzas da queima de eucalipto e, a seguir, expostas sob diferentes condições de posicionamento, voltadas para as orientações norte, sul, leste e oeste, à 0º, 45º e 90º. Ao longo do período de exposição, foram realizadas leituras cromáticas (sistema CIELab) na superfície das amostras, tendo em vista a descoloração dos manchamentos aplicados. Para aquelas manchadas com Rodamina B, a degradação do corante se mostrou mais eficiente nas argamassas com maiores teores de TiO2 e nas configurações de posicionamento que recebem maior incidência de radiação solar. As coberturas de pasta apresentaram valores mais elevados de variação de cor (ΔE) e refletância (L*), na comparação à aplicação do TiO2 como cobertura de argamassa ou incorporado à mistura − métodos os quais se mostraram resultados equivalentes. / Building façades are commonly exposed to polluting agents generated by vehicles and industries exhausts, which cause stains on their surfaces and increase efforts and costs both for cleaning and maintenance. Facades are attractive to photocatalytic materials usage, which transform pollutants to innocuous products. The addition of titanium dioxide (TiO2) to white cement mortars and concretes develops self-cleaning surfaces which are capable to reduce stains and maintain their original color along the time. However, efficiency and economy in the use of photocatalytic materials in real applications are strongly affected by the availability of suitable ultraviolet radiation to activate them. This thesis aims to evaluate the self-cleaning ability of TiO2-containing mortars and coatings (paste or mortar) exposed to controlled positioning settings in the urban environment of Porto Alegre, Brazil. Mortars and coatings were prepared containing different additions of TiO2 and then were soiled by Rhodamine B (RhB) or burning ashes of eucalyptus sludge. Samples were exposed under outdoor conditions facing north, south, east and west orientations, 0º, 45º or 90º slopes. During the exposure test, discoloration effect on samples' surface was monitored by colorimetric measurements (CIELab color space) using a portable spectrophotometer. A final analysis was performed at the end of the measurements, including statistical tests. Self-cleaning ability was better seen both for higher additions of TiO2 and settings which receive higher intensities of solar radiation. Cement paste coatings showed higher values both of color change and reflectance when compared to mortar coatings or TiO2 added to the mixture − which performed equivalent results.

Ao longo do tempo, os revestimentos de fachada permanecem expostos a diversos agentes de degradação, sejam eles associados aos próprios materiais empregados ou a fatores externos. Tal exposição implica em manchas formadas a partir da deposição de partículas poluentes na superfície dos revestimentos, elevando seus custos para limpeza e manutenção. Uma vez que permanecem expostas à radiação solar, as fachadas se mostram atraentes ao uso de materiais fotocatalíticos, os quais catalizam a mineralização de agentes poluentes, transformando-os em produtos inócuos. A adição de dióxido de titânio (TiO2) a argamassas e concretos de cimento branco desenvolve superfícies autolimpantes, reduzindo a formação de manchas e mantendo sua coloração original ao longo do tempo. No entanto, a eficiência e a economia no uso de materiais fotocatalíticos em aplicações reais é fortemente afetada pela disponibilidade da radiação ultravioleta adequada para ativá-los. Portanto, o presente trabalho busca avaliar a capacidade autolimpante de argamassas e coberturas fotocatalíticas de TiO2 expostas a diferentes configurações de posicionamento no microclima urbano da cidade de Porto Alegre. Para isto, foram confeccionadas amostras de argamassa e coberturas de pasta ou argamassa contendo diferentes teores de TiO2, as quais foram manchadas com Rodamina B e lodo de cinzas da queima de eucalipto e, a seguir, expostas sob diferentes condições de posicionamento, voltadas para as orientações norte, sul, leste e oeste, à 0º, 45º e 90º. Ao longo do período de exposição, foram realizadas leituras cromáticas (sistema CIELab) na superfície das amostras, tendo em vista a descoloração dos manchamentos aplicados. Para aquelas manchadas com Rodamina B, a degradação do corante se mostrou mais eficiente nas argamassas com maiores teores de TiO2 e nas configurações de posicionamento que recebem maior incidência de radiação solar. As coberturas de pasta apresentaram valores mais elevados de variação de cor (ΔE) e refletância (L*), na comparação à aplicação do TiO2 como cobertura de argamassa ou incorporado à mistura − métodos os quais se mostraram resultados equivalentes. / Building façades are commonly exposed to polluting agents generated by vehicles and industries exhausts, which cause stains on their surfaces and increase efforts and costs both for cleaning and maintenance. Facades are attractive to photocatalytic materials usage, which transform pollutants to innocuous products. The addition of titanium dioxide (TiO2) to white cement mortars and concretes develops self-cleaning surfaces which are capable to reduce stains and maintain their original color along the time. However, efficiency and economy in the use of photocatalytic materials in real applications are strongly affected by the availability of suitable ultraviolet radiation to activate them. This thesis aims to evaluate the self-cleaning ability of TiO2-containing mortars and coatings (paste or mortar) exposed to controlled positioning settings in the urban environment of Porto Alegre, Brazil. Mortars and coatings were prepared containing different additions of TiO2 and then were soiled by Rhodamine B (RhB) or burning ashes of eucalyptus sludge. Samples were exposed under outdoor conditions facing north, south, east and west orientations, 0º, 45º or 90º slopes. During the exposure test, discoloration effect on samples' surface was monitored by colorimetric measurements (CIELab color space) using a portable spectrophotometer. A final analysis was performed at the end of the measurements, including statistical tests. Self-cleaning ability was better seen both for higher additions of TiO2 and settings which receive higher intensities of solar radiation. Cement paste coatings showed higher values both of color change and reflectance when compared to mortar coatings or TiO2 added to the mixture − which performed equivalent results.

As fachadas das edificações, ao longo de sua vida útil, sofrem degradação devido a ataques de agentes químicos e à deposição de partículas na sua superfície. Como consequências, há perdas no desempenho de seus materiais e a desfiguração estética das fachadas por meio de manchas, implicando em ações de reparo que envolvem custos elevados. Os produtos atualmente disponíveis no mercado brasileiro com objetivo de evitar o manchamento de fachadas têm baixa eficiência, sendo que os principais deles adotam a técnica do pós-tratamento com hidrofugantes, os quais geralmente alteram a coloração do substrato e podem ser a origem de novas patologias. Usufruindo de novas tecnologias, o dióxido de titânio (TiO2) apresenta-se como material nanométrico amplamente estudado na área científica, sendo potencialmente utilizado como fotocalisador. O presente trabalho verificou a possibilidade de obtenção de superfícies autolimpantes a partir da adição de TiO2 em revestimentos de argamassa branca. Estas, a partir de propriedades fotocatalíticas do TiO2 podem ser tornar autolimpantes sob ação da radiação solar (UV) e da chuva. Foram confeccionadas argamassas de traço 1:2 e 1:3, com adições de 0%, 5% e 10% de TiO2 em relação à massa de cimento, com consistência fixa. As amostras foram aspergidas com diferentes agentes manchantes: azul de metileno, particulado de poluição, produto de corrosão, pichação; e sem manchamento (referência). Após, estas amostras foram expostas nas condições ambientais da cidade de Porto Alegre. Ao longo de 84 dias, foram realizadas leituras com espectrofotômetro portátil para avaliar o efeito autolimpante. Também foram verificadas as propriedades físico-mecânicas das argamassas. Os resultados apontaram que argamassas com adição de TiO2 necessitaram maior quantidade de água, apresentaram maior densidade no estado fresco e menor teor de ar incorporado. Ainda, a resistência à compressão foi elevada para o traço mais rico (1:2) e mantida constante para o traço pobre (1:3). Além disso, se mostraram mais claras/brancas quanto maior a porcentagem de adição. O efeito autolimpante pode ser percebido mais facilmente na mancha de azul de metileno, porém, a limpeza ocorreu tanto em argamassas com adição de TiO2, quanto em argamassas sem a adição. Em manchas que geraram uma película sobre a placa, o efeito autolimpante foi dificultado. / The facades of buildings, during their lifespan, suffer degradation due to attacks of chemical agents and due to deposition of particles on their surface. As consequences, there are losses on the performance of their materials and aesthetics disfiguration of the facades by stains, implying repairing actions involving high costs. The products available nowadays on the brasilian market with the purpose to avoid the staining of the facades have low efficiency, and the main products between them adopt the technique of post-treatment with hydrophobing, which generally modify the colour of the substrate and which can originate new pathologies. Taking advantage of new technologies, the titanium dioxide (TiO2) appears as a nanometric material widely studied in the scientific area, being pottentialy used as photocatalyser. The present work has verified the possibility of obtention of self-cleaning surfaces after addition of TiO2 in white mortar coverings. Those, from photocatalyser properties of the TiO2 can become self-cleaning under the action of solar radiation (UV) and rain. There were prepared mortars of trace 1:2 and 1:3, with additions of 0%, 5% and 10% of TiO2 in relation of the cement weight, with steady consistency. The samples were sprinkled with different staining agents: methylene blue, pollution particulates, corrosion product, graffiti; and without stains (reference). After that, these samples were exposed to the ambiental conditions of the city of Porto Alegre. Through 84 days, scannings were made with portable spectrophotometer to evaluate the self-cleaning effect. The physicalmechanical properties of the mortars were also verified. The results point out that mortars with addition of TiO2 required a bigger amount of water, they presented bigger density in the fresh state and smaller contents of incorporated air. Besides, the compression resistance was high to the richest trace (1:2) and remained constant to the poor trace (1:3). Moreover, they have showed themselves more clear/white as bigger was the percentage of addition. The self-cleaning effect can be more easily noticed on the methylene blue stain, however, the cleaning occurred both in mortars with addition of TiO2 and in mortars without the addition. In stains which generate a film above the plate, the self-cleaning effect was hampered.

Content: Nanoparticles showed a huge potential for new properties development in many economic sectors like electronics, medicine, textile, waste water treatment etc. The modification of surface functionality by using low concentrations of nanomaterials opens the possibility of lowering the ecological impact of chemical materials based on volatile organic compounds. The objectives of our research were related to the use of commercial nanoparticles based on Ag and TiO2 with average particle size of 8 nm for leather surface functionalization and the investigation of the cytotoxicological impact of nanoparticle concentrations on human skin cells. The practical implications of the approach consist of multifunctional leather surface development, leather durability and comfort increase by generating antimicrobial and self-cleaning properties. The relation between leather functionality and the cytotoxicity concentration limit of nanomaterials was the hypothesis of our research. The main procedures for leather surface covering followed the classical recipes based on surface spraying with film forming composites with nanoparticle content. The optimized technology was evaluated by leather surface analyses regarding the antimicrobial (SR EN ISO 20645) and self-cleaning properties under UV and visible light exposure as compared to leather surface covered without nanoparticles. The cytotoxicity tests were performed by incubation of keratinocytes (Human immortalized keratinocytes-HaCaT) with different concentrations of nanoparticles for 48 hours and measurement of cell viability by MTT (3-[4,5-dimethylthiazol- 2-yl]-2,5-diphenyltetrazolium bromide) assay protocol. Other tests were devoted to leather wearing simulation in order to estimate the potential transfer of nanoparticles on human skin and the health and safety impact. These simulations were based on rubbing test (SR EN ISO 11640) followed by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) analyses and by leachability tests (SR EN ISO 4098) performed in artificial perspiration solution followed by inductively coupled plasma -mass spectrometry (ICP-MS) analyses, according to SR EN ISO 17294-2 and SR EN ISO 16171. The main conclusions of our research showed that it is possible to add multifunctional value to leather surface by using Ag and TiO2 nanoparticles with low impact on safety and health. Acknowledgements: The works were funded by UEFISCDI and MCI, project number PNIII_15/2015-2018 under the frame of SIINN, the ERA-NET for a Safe Implementation of Innovative Nanoscience and Nanotechnology program and respectively, PN 19 XX 05 01 project/2019 under Nucleus program TEX-PELVISION 2022 Take-Away: - antimicrobial and self-cleanning nanoparticles for leather surface finishing - Ag and TiO2 nanoparticle cytotoxicity tests for human skin cells - multifunctional surface properties with low cytotoxicological impact

With power conversion efficiency surpassing the 10% milestone for commercialization, photovoltaic technology based on solution-processable polymer solar cells (PSCs) provides a promising route towards a cost-efficient strategy to address the ever-increasing worldwide energy demands. However, to make PSCs successful, challenges such as insufficient light absorption, high maintenance costs, and relatively high production costs must be addressed. As solutions to some of these problems, the unique properties of nanostructured materials and complimentary light absorption in multi-junction device structure could prove to be highly beneficial. As a starting point, integrating nanostructure-based transparent self-cleaning surfaces in PSCs was investigated first. By controlling the length of the hydrothermally grown ZnO nanorods and covering their surface with a thin layer of chemical vapor-deposited SiO2, a highly transparent and UV-resistant superhydrophobic surface was constructed. Integrating the transparent superhydrophobic surface in a PSC shows minimal impact on the figure of merit of the PSC. To address the low mechanical durability of the transparent superhydrophobic surface based on SiO2-coated ZnO nanorods, a novel method inspired by the water condensation process was developed. This method involved directly growing hollow silica half-nanospheres on the substrate through the condensation of water in the presence of a silica precursor. Benefit from the decreased back scattering efficiency and increased light transport mean free path arise from the hollow nature, a transparent superhydrophobic surface was realized using submicrometer sized silica half-nanospheres. The decent mechanical property of silica and the “direct-grown” protocol are expected to impart improved mechanical durability to the transparent superhydrophobic surface. Regarding the application of multi-junction device structure in PSCs, homo multi-junction PSCs were constructed from an identical polymer absorber, in which the homo-tandem device showed an enhanced power conversion efficiency (PCE) (8.3% vs 7.7%) relative to the optimized single junction PSC. The high open voltage (>1.8 V) achieved in homo-tandem PSCs allowed for water splitting with an estimated solar-to-fuel conversion efficiency of 6%. Lastly, a hybrid tandem cell was also constructed using a polymer and a colloidal quantum dot subcell. Different hybrid tandem device architectures were proposed and show a promising PCE of 6.7%.

Det har blivit allt vanligare att sjukvården i Sverige flyttas ut till vårdtagarnas hem. De kan med hjälp av hemtjänst få bo kvar i sina egna hus längre men samtidigt få den hjälp de behöver. År 2007 använde sig totalt 153 723 personer av dessa tjänster runt om i Sverige. De plagg som personalen bär utsätts för många olika typer av yttre påfrestningar vid hembesök hos vårdtagarna. Smittspridning inom vården sker främst via personalens händer och kläder.Nanoteknologi är en framväxande teknik som gått på högvarv inom många olika områden under det senaste årtiondet. Forskning pågår som involverar nanoteknologi för att förbättra egenskaper eller för att skapa funktionella textilier som kan få egenskaper som antibakteriella, lättrengörliga, vatten- och fläckavvisande samt luktfria. Syftet är att underska om nanoteknik kan användas i det textila materialet i arbetskläder inom hemtjänsten för att bättre stå emot yttre påfrestningar. Det finns idag många problem inom området arbetskläder och hygien, vi vill därför undersöka om denna teknik kan vara en av lösningarna.Nanoteknik för textilier har två inriktningar. Den ena strävar främst efter att använda nanostorleken för att skapa nanostrukturer under själva tillverkningsprocessen, medan den andra är inriktad mot ytbehandlingsprocesser. I rapporten ligger fokus på beläggningsmetoden och de självrengörande och antibakteriella egenskaperna som kan skapas hos ett material.Vi kom fram till att det bästa alternativet för dessa typer av plagg skulle vara att tillföra antibakteriella egenskaper. De kan då beläggas med antingen titandioxid, zinkoxid eller silver då det är väl beprövade ämnen som är bevisade att fungera och ger just dessa egenskaper.Med hjälp av empiriska undersökningar kunde vi ge svar på vad arbetskläder utsätts för under en arbetsdag. Utifrån dessa resultat kunde vi rikta in vår teoretiska referensram på de områden som skulle kunna vara intressanta för att uppnå syftet. Tillslut kom vi fram till att nanoteknik kan bidra till att skapa kläder som bättre står emot yttre påfrestningar och ger bättre hygieniska förhållandeIt is increasingly common for healthcare in Sweden to move out to the residents&apos; homes. They can use homecare to continue living in their own house, but at the same time get the help they need. In 2007 the total of 153 723 people were in use of these services across Sweden.The garments that the staff is wearing get exposed to many different types of external shocks on home visits. Spread of infection in health care is primarily through the staff&apos;s hands and clothes.Nanotechnology is an emerging technology that has been booming in many areas over the past decade. Research is underway involving nanotechnology to improve properties or to create functional fabrics that can have antibacterial properties, easy to clean, water- and stain resistant and odor-free. The aim is to investigate whether nanotechnology can be used in the textile material in assisted living to better withstand external shocks. Today there are many problems in the field of workwear and hygiene, we therefore wish to consider whether this technology can be one of the solutions. Nanotechnology for textiles has two directions. On one striving primarily for the use of nanosize to create nanostructures during the manufacturing process, while the other is focused on finishing processes. The report focuses on the coating method and the self-cleaning and antibacterial properties that can be created in a material.We concluded that the best thing for these types of garments would be that they had antibacterial properties. They are then coated with either titaniumdioxide, zincoxide or silver when it is proven substances which are proven to work and provide these same qualities. With help from our empirical studies, we could provide answers to what the clothes get exposed to during a day of work. Based on these results, we could focus our theoretical framework in the areas that could be relevant to the objectives. Eventually, we concluded that nanotechnology could help to create cloths that better withstand external shocks and improves the hygienic conditions. / Program: Textil produktutveckling med entreprenörs- och affärsinriktning

Selbstreinigende, ultrahydrophobe Oberflächen lassen sich in der Technik vielfältig einsetzen. Das ultrahydrophobe Verhalten beruht einerseits auf einer Rauigkeit im μm-Bereich und andererseits auf der chemischen Zusammensetzung der Oberfläche. Durch den gegebenen Oberflächenaufbau sind derartige Materialien jedoch empfindlich gegen Verschleiß. In diesem Beitrag wird ein Schichtverbund bestehend aus Aluminiumoxid und zwei polymeren Komponenten vorgestellt. Die Aluminiumoxidschicht wird auf dem Wege der anodischen Oxidation erzeugt. Dieses seit langem bekannte Verfahren ermöglicht nicht nur die Oxidation der Aluminiumoberfläche, sondern gestattet es, auch, definierte Oberflächenprofile einzustellen. Durch den gezielten Einbau des hochmolekularen Polymers Chitosan in die mikroprofilierte Aluminiumoxidschicht wurde eine mechanische Stabilisierung der Schicht im Sinne eines anorganisch-organischen Composites erreicht. Außerdem dienten die Amino-Seitengruppen des Chitosans als reaktives Interface für die notwendige chemische Hydrophobierung und als Reaktionszentrum für Vernetzungen, wodurch eine weitere mechanische Stabilisierung bewirkt wird. Der Schichtaufbau hat wesentlichen