Nanocompósitos de PMMA/ argila montmorilonita foram obtidos por fotopolimerização in situ. O metacrilato de metila foi polimerizado na presença de argilas modificadas usando Tioxantona (TX) e etil 4-(dimetilamino) benzoato (EDB) como sistema fotoiniciador. As argilas montmorilonitas SWy-1 modificadas, SWy-1-C8 e SWy-1-C16, foram preparadas pela troca de íons com brometo de octiltrimetilamônio (C8) e brometo de hexiltrimetilamônio (C16), respectivamente. A difração de raios-X indicou que os compósitos de PMMA/argila podem ter estruturas intercaladas ou esfoliadas, ou mesmo uma mistura de estruturas em camadas esfoliada e parcialmente intercalada. A estrutura de cada nanocompósito depende da concentração de argila e do solvente utilizado na preparação. A influência da concentração de argila organofílica, natureza do solvente e tipo de argila nas propriedades térmicas e mecânicas foi estudada por análise termogravimétrica e análise dinâmico-mecânica. Todos os nanocompósitos preparados em acetonitrila exibiram melhora da sua estabilidade térmica, principalmente devido à interação entre a argila e o polímero que é maximizada através da estrutura da argila esfoliada. No caso do PMMA e nanocompósitos sintetizados em etanol, a estabilidade térmica do polímero e nanocompósitos foi praticamente a mesma, uma vez que a estrutura da argila é predominantemente do tipo intercalada. Na velocidade de polimerização observou-se que os fatores que mais influenciaram foram a concentração de argila e o tipo de solvente. A argila proporciona a formação de microambientes que estabilizam o estado excitado do iniciador formando mais radicais livres e consequentemente aumentando a velocidade polimerização. A utilização da acetonitrila, a qual é um melhor solvente para o PMMA proporcionou massas molares menores. A degradação foto-oxidativa dos nanocompósitos de PMMA/ argila foi investigada utilizando cromatografia de exclusão de tamanho (SEC). Foram encontradas evidências de que o PMMA e nanocompósitos degradam por cisões aleatórias de cadeias. A polidispersidade aumentou após a irradiação e o coeficiente de degradação de PMMA puro é de até seis vezes maior do que para os nanocompósitos. O efeito sobre os coeficientes de fotodegradação da concentração de argila, tipo argila (argila modificada por agentes tensoativos com diferentes comprimentos de cadeias de alquílica) e o solvente utilizado para a dispersão de argila orgânica, também foram estudados. / Montmorillonite clay/PMMA nanocomposites were obtained by in situ photopolymerization. Methyl methacrylate was polymerized in the presence of modified clays using thioxanthone (TX) and ethyl 4-(dimethylamino) benzoate (EDB) as photoinitiating system. The SWy-1 montmorillonite modified clays, SWy-1-C8 and SWy-1-C16, were prepared by ion exchange with octyltrimethylammonium bromide (C8) and hexyltrimethylammonium bromide (C16), respectively. X-ray diffraction indicated that clay/PMMA composites have intercalated or exfoliated structures, or even a mixture of exfoliated and partially intercalated structure layers. The structure of each particular nanocomposite depends on the clay loading and the solvent used for the preparation.The influences of organoclay loading, solvent nature and clay type on thermal and mechanical properties were studied by thermogravimetric analysis and dynamic mechanical analysis. All the nanocomposites prepared in acetonitrile exhibited improvement in their thermal stability, mainly due to the interaction between the clay and the polymer which is maximized by the exfoliated clay structure. In the case of PMMA and nanocomposites synthesized in ethanol, the thermal stability of polymer and nanocomposites remained practically the same once the clay structure is predominantly of the intercalated type. It was observed that the factors that most influenced the polymerization rate were the concentration of clay and type of solvent. The clay provides the formation of microenvironments that stabilizes the excited state of the initiator forming free radicals and consequently increasing the polymerization rate. The use of acetonitrile, which is a better solvent for PMMA gave the lowest molar weight. The photooxidative degradation of clay/PMMA nanocomposites has been investigated using size exclusion chromatography (SEC). Evidence was found that PMMA and composites degrade by random chain scissions. The polydispersity increases after irradiation and the degradation rate coefficient for pure PMMA is up to 6 times larger than that for the composites. The effect on the photodegradation rate coefficients of the clay content, clay type (clay modified by surfactants with different lengths of alkyl chains) and solvent used for dispersion of organic clay were also studied. The relationship of these parameters on the photodegradation process was statistically evaluated using a two-level factorial design.

Orientador: Leinig Antônio Perazolli / Resumo: O presente trabalho buscou desenvolver fotocatalisadores cerâmicos por meio da produção de heterojunções inovadoras à base de SrTiO3, TiO2 e CaO, que tiveram suas fotoatividades avaliadas pela descoloração do corante Rodamina B (RhB) e pela obtenção de biodiesel, utilizando luz ultravioleta. As amostras TiO2, CaO e SrTiO3 foram obtidas pelo método de precursores poliméricos, método Pechini, e as heterojunções TiO2/SrTiO3, CaO/SrTiO3 e CaO/CaTiO3 foram preparados por rota sol-gel. Após síntese e tratamento térmico, as amostras foram caracterizadas por difração de Raios-X (DRX) para verificar as fases cristalinas formadas, por espectroscopia de infravermelho com transformada de fourier (FT-IR) e termogravimetria/análise térmica diferencial (TG/DTA) para verificar e quantificar a formação de CaCO3 e Ca(OH)2, por espectroscopia de refletância difusa (UV/Vis/NIR DRS) para determinar a energia de band gap, por Brunauer, Emmett e Teller (B.E.T.) para determinar a área específica, por microscopia eletrônica de varredura acoplada a espectroscopia de energia dispersiva de Raios-X (FE-SEMEDS) para estimar o tamanho das partículas, sua morfologia e composição elementar, por espectroscopia de fotoelétrons excitados por Raios-X (XPS) para conhecer a composição elementar presente na superfície da amostra e seus estados de oxidação, por espectroscopia de fotoluminescência (PL) para verificar a formação de defeitos estruturais, por microscopia eletrônica de transmissão de alta resolução (HRTE... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work aimed to develop ceramic photocatalysts through the production of innovative SrTiO3, TiO2 and CaO based heterojunctions, which had their photoactivities evaluated by the discoloration of Rhodamine B (RhB) dye and by obtaining biodiesel using UV light. TiO2, CaO and SrTiO3 samples were obtained by polymeric precursor method, Pechini method, and TiO2/SrTiO3, CaO/SrTiO3 and CaO/CaTiO3 heterojunctions were prepared by sol-gel route. After synthesis and heat treatment, the samples were characterized by X-ray diffraction (XRD) to verify the crystalline phases formed, fourier transform infrared spectroscopy (FT-IR) and thermogravimetry/differential thermal analysis (TG/DTA) to verify and quantify the formation of CaCO3 and Ca(OH)2, diffuse reflectance spectroscopy (UV/Vis/NIR DRS) to determine band gap energy, Brunauer, Emmett e Teller (B.E.T.) to determine specific area, field emission scanning electron microscopy coupled X-ray dispersive energy spectroscopy (FE-SEM-EDS) to estimate particle size, morphology and elemental composition, X-ray photoelectron spectroscopy (XPS) to know the elemental composition present on the sample surface and oxidation states, photoluminescence spectroscopy (PL) to verify the formation structural defects, high resolution transmission electron microscopy (HRTEM) to confirm the formation of heterojunction. Rhodamine B discoloration was measured by UV/Vis molecular absorption spectroscopy and the conversion of oil to biodiesel was analyz... (Complete abstract click electronic access below) / Doutor

Mesoporous silica has shown great potential as an adsorbent for environmental contaminants and as a host for imaging and therapeutic agents. Mesoporous silica materials have a high surface area, tunable pore sizes and well defined surface properties which are governed by the surface hydroxyl groups. Surface modification of the mesoporous silica can tailor the adsorption properties for a specific metal ion or a small drug molecule by providing better sites for chelation or electrostatic interactions. Iron oxide / mesoporous silica core shell materials couple the favorable properties of both the iron oxide and mesoporous silica materials. The core-shell materials have higher adsorption properties compared to the parent material. With magnetic iron oxide nanoparticle cores, an additional magnetic property is introduced that can be used as magnetic recovery or separation. Heavy metals such as Chromium (Cr) and Arsenic (As) discharged from residential and environmental sources pose a serious threat to human health as well as groundwater pollution. In this thesis, iron oxide nanoparticles and nanofibers were coated with mesoporous silica and functionalized with (3-aminopropyl)triethoxysilane (APTES) using the post synthesis grafting method. The parent and the functionalized magnetic silica samples were characterized using powder X-ray diffraction (pXRD), thermal gravimetric analysis (TGA), Fourier Transform Infrared (FTIR) spectroscopy and nitrogen adsorption desorption isotherms for surface area and pore volumes. These materials were evaluated for Cr(III) and As(III)/As(V) adsorption from aqueous solutions in the optimum pH range for the specific metal. The aminopropyl functionalized magnetic mesoporous silica displayed the highest adsorption capacity for Cr(III) and Cu(II) of all the materials evaluated in this study. The high heavy metal adsorption capacity was attributed to a synergistic effect of iron oxide nanoparticles and amine functionalization on mesoporous silica as well as a judicious choice of pH. Modified magnetic mesoporous silica material was also found to have high adsorption capacity for high and low pH aqueous solutions of Uranium (VI). Tuning the loading and release of a small drug molecule (5-FU) onto these iron oxide/ mesoporous silica core-shell materials was also investigated. The polarity of the solvent used to load 5-FU onto the host had an impact not only on the loading but also on the release percentage of 5-FU. The synthesis of a novel core-shell material with a hematite nanofiber core and a SBA type mesoporous silica shell was also explored.

The effect of incorporation two clays; layered double hydroxides (LDH) and montmorillonite layered silicates (MLS) in linear low density polyethylene (PE) matrix was investigated. MLS and LDH were added of 5, 15, 30 and 60 weight percent in the PE and compounded using a Brabender. Ground pellets were subsequently compression molded. Dispersion of the clays was analyzed using optical microscopy, SEM and XRD. Both the layered clays were immiscible with the PE matrix and agglomerates formed with increased clay concentration. The thermal properties were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Both clays served as nucleation enhancers increasing recrystallization temperatures in the composites. Flame retarding properties were determined by using the flammability HVUL-94 system. LDH indicated better flame retarding properties than MLS for PE. The char structure was analyzed by environmental scanning electron microscopy. Mechanical properties were studied by tensile testing and Vickers microhardness testing apparatus.

The effect of incorporation of montmorillonite layered silicate (MLS) on poly (ethylene terephthalate) (PET) matrix was investigated. MLS was added in varying concentration of 1 to 5 weight percent in the PET matrix. DSC and polarized optical microscopy were used to determine the crystallization effects of MLS addition. Non isothermal crystallization kinetics showed that the melting temperature and crystallization temperature decrease as the MLS percent increases. This delayed crystallization along with the irregular spherulitic shape indicates hindered crystallization in the presence of MLS platelets. The influence of this morphology was related with the fracture toughness of PET nanocomposites using essential work of fracture coupled with the infra red (IR) thermography. Both the essential as well as non essential work of fracture decreased on addition of MLS with nanocomposite showing reduced toughness.

The aim of the master’s thesis is study of polymer composite system with the addition of graphite, production of test specimen and determination of their mechanical and thermal properties. The theoretical part deals with graphene, its structure, preparation and properties. Subsequently, it deals with functionalization and derivates and nanocomposites polymers with the addition of graphene are generally analyzed. The experimental deals with the preparation of selected specimens. Tensile and laternal tests and DMA were used for study.

Water pollution is a major environmental issue, which mankind is facing in modern times. Pollutants (especially dyes, antibiotics and bacteria) released by human activity into wastewater are harmful to humans, animals and water bodies. Therefore, it is urgent to remove these pollutants from wastewater. Amongst conventional wastewater tertiary treatment techniques, there are adsorption and advanced oxidation processes (AOPs) including photocatalysis. These two methodologies can have important benefit from the use of nanomaterials. Despite the plethora of reports about adsorption or photocatalysis for wastewater treatment, there are still some issues in this field, i.e.: (1) In photocatalysis, one of the most common photocatalysts, titanium dioxide (TiO2), has been widely used to degrade organic pollutants in water, but it has the limitation to be operated by ultraviolet (UV) light and, therefore, by means of a non-sustainable and high associated cost methodology. (2) Most of the literature presented one material to remove only one kind of pollutant at a time. However, as we all know, wastewater is a complex matrix comprising several species. (3) Most researchers have used only one technique, e.g. adsorption or photocatalysis, to treat wastewater. However, adsorption or photocatalysis has its own limitations, which may be overcome by their combined use. Only few researchers combined adsorption and photocatalysis for wastewater treatment and this field is still in its infancy. (4) Few research reports deal with nanocomposites simultaneously possessing antibacterial activity and the ability to remove organic pollutants of different chemical composition and properties, such as dyes and antibiotics. (5) After wastewater treatment, the recovery and the reuse of the photocatalytic materials used as slurry photocatalysts are generally problematic. The aim of this thesis is to tackle some of these issues by developing new multifunctional nanocomposites capable of removing different kinds of pollutants – namely dyes, antibiotics and bacteria – from wastewater through a sustainable and cost-effective treatment. Moreover, the new nanocomposites will have to be easy to recover and reusable. In this context, different kinds of polymer-based magnetic nanocomposites comprising a core of Fe3O4/poly(N-isopropylacrylamide-co-methacrylic acid) (Fe3O4/P(NIPAM-co-MAA)) microspheres were prepared. To reach this aim, the different kinds of nanomaterials to be combined in the composites were synthesized and thoroughly studied. The first material is silver-titanium dioxide nanoparticles (Ag-TiO2 NPs), which were prepared by synthesizing Ag NPs on the surface of commercial TiO2 P25 via a photochemical reduction method. Compared with TiO2 P25, the prepared Ag-TiO2 NPs showed enhanced visible light photocatalytic degradation of the two antibiotics ciprofloxacin (CIP) and norfloxacin (NFX). Besides, the visible light photocatalytic mechanism of Ag-TiO2 NPs underlying the photodegradation of CIP was studied. Moreover, recycling experiments of Ag-TiO2 NPs demonstrated that Ag-TiO2 NPs could be reused. Last but not least, Ag-TiO2 NPs displayed an excellent ability to inhibit the growth of Escherichia coli (E. coli). Subsequently, Fe3O4/P(NIPAM-co-MAA) microspheres were prepared and characterized according to a previously published procedure. After the single components were obtained, studied and characterized, a large part of the thesis was devoted to the preparation of the Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites, which showed excellent adsorption, photocatalytic and antibacterial activities. The new multifunctional nanocomposites could not only adsorb dyes like basic fuchsin (BF), but also degrade antibiotics like CIP and NFX under visible light irradiation. More importantly, the nanocomposites could adsorb and degrade the pollutants mixture (BF and CIP) in water under visible light irradiation and showed good antibacterial activity towards E. coli. Due to the superparamagnetic properties of Fe3O4 NPs, the nanocomposites could be easily reused. Finally, another material, polyamidoamine (PAMAM) dendrimer-grafted Fe3O4/P(NIPAM-co-MAA) nanocomposite, was prepared by combining the previously prepared Fe3O4/P(NIPAM-co-MAA) microspheres with dendrimers. The obtained nanocomposites showed excellent adsorption activities towards differently charged dyes. In particular, thanks to the carboxylic groups on MAA in the Fe3O4/P(NIPAM-co-MAA) microspheres, the nanocomposites could adsorb positively charged dyes (e.g. BF), while, thanks to the amino groups on PAMAM dendrimers, also negatively charged dyes such as methyl orange (MO) could be adsorbed. Due to the superparamagnetic properties of the Fe3O4 NPs, the nanocomposites could be easily reused. In conclusion, these multifunctional nanocomposites in this thesis work overcame some current limitations, which hinder the use of nanomaterials in wastewater treatment applications, thereby providing an ecologically promising and effective method for reducing water pollution.:Declaration of primary authorship iii Acknowledgments v Abstract vii Kurzfassung ix List of figures xvii List of tables xxiii Nomenclature xxv Chapter 1: Introduction 1 1.1 Motivation 1 1.2 Challenges 1 1.3 Aim of the thesis 2 1.4 Outline of the thesis 3 Chapter 2: Fundamentals 5 2.1 Pollutants in wastewater 5 2.2 Adsorption technique for wastewater treatment 6 2.2.1 Activated carbon 7 2.2.2 Zeolites 7 2.2.3 Polymers 8 2.3 Photocatalysis 11 2.3.1 History of TiO2 in photocatalysis 12 2.3.2 TiO2 crystalline phases 12 2.3.3 TiO2 photocatalytic mechanism under UV light irradiation 13 2.3.4 Parameters influencing the photocatalytic efficiency of TiO2 16 2.4 Development of visible light-responsive TiO2 photocatalysts 19 2.4.1 Non-metal doping 20 2.4.2 Metal doping 20 2.4.3 Dye sensitization 21 2.4.4 Coupled semiconductors 22 Chapter 3: Materials and experimental methods 23 3.1 Materials 23 3.2 Protocols 27 3.2.1 Preparation of Ag-TiO2 NPs 27 3.2.2 Preparation of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 27 3.2.3 Preparation of PAMAM dendrimer-grafted Fe3O4/P(NIPAM-co-MAA) nanocomposites 28 3.3 Characterization methods 29 3.3.1 High Resolution Transmission Electron Microscopy (HRTEM) 30 3.3.2 Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy 30 3.3.3 X-ray powder Diffraction (XRD) 30 3.3.4 UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS) 30 3.3.5 Fluorometer 31 3.3.6 Brunauer-Emmett-Teller (BET) surface area analysis 31 3.3.7 Vibrating Sample Magnetometer (VSM) 31 3.3.8 Thermal Gravimetric Analysis (TGA) 31 3.4 Photocatalytic activity measurements 31 3.4.1 Visible light photocatalytic activity of TiO2 P25 and Ag-TiO2 NPs 32 3.4.2 Visible light photocatalytic investigations of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 33 3.5 Adsorption capacity measurements 34 3.5.1 Adsorption capacity of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 34 3.5.2 Adsorption capacity of PAMAM dendrimer-grafted Fe3O4/ P(NIPAM-co-MAA) nanocomposites 35 3.6 Antibacterial activity tests 37 3.6.1 Ag-TiO2 NPs antibacterial activity investigations 38 3.6.2 Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites antibacterial activity investigations 38 Chapter 4: Ag-TiO2 NPs 41 4.1 Characterization of Ag-TiO2 NPs 42 4.2 Photocatalytic activity of Ag-TiO2 NPs 47 4.2.1 Assessment of the photocatalytic activity of Ag-TiO2 NPs 47 4.2.2 Reusability of Ag-TiO2 NPs 50 4.2.3 Photocatalytic mechanism of Ag-TiO2 NPs 51 4.3 Antibacterial properties of Ag-TiO2 NPs 53 4.4 Summary 54 Chapter 5: Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 57 5.1 Characterization of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 58 5.2 Adsorption of dyes by Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 64 5.3 Degradation of antibiotics by Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 68 5.4 Reusability of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 72 5.5 Antibacterial activity of Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 74 5.6 Adsorption and degradation of a mixture of pollutants by Fe3O4/P(NIPAM-co-MA A)/Ag-TiO2 nanocomposites 75 5.6.1 Adsorption and degradation of BF by Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 75 5.6.2 Adsorption and degradation of CIP by Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 78 5.6.3 Adsorption and degradation of a mixture of BF and CIP by Fe3O4/P(NIPAM-co-MAA)/Ag-TiO2 nanocomposites 80 5.7 Summary 86 Chapter 6: PAMAM dendrimer-grafted Fe3O4/P(NIPAM-co-MAA) nanocomposites 89 6.1 Characterization of PAMAM dendrimer-grafted Fe3O4/P(NIPAM-co-MAA) nanocomposites 89 6.2 Adsorption capacity of different nanocomposites towards dyes 95 6.2.1 Adsorption of positively charged dye BF by different nanocomposites 96 6.2.2 Adsorption of negatively charged dye MO by different nanocomposites 97 6.2.3 Adsorption of BF and MO by G51P0.8 and G51P0.5 nanocomposites 98 6.2.4 Adsorption kinetics and isotherm of G51P1 nanocomposites 101 6.3 Reusability 105 6.4 Summary 106 Chapter 7: Conclusions and outlook 109 7.1 Conclusions 109 7.2 Outlook 111 Appendix 113 A1 Calibration curves 113 A2 Assessment of the photocatalytic activity of Ag-TiO2 NPs 114 References 117 Scientific output 141 Curriculum vitae 143

Orientador: Fauze Ahmad Aouada / Resumo: Com o objetivo de aplicar agroquímicos de uma forma controlada, e reduzir os danos à saúde e ao meio ambiente causados por estes, foram desenvolvidos neste trabalho, dois novos hidrogéis a partir de dois polissacarídeos diferentes carboximetilcelulose (CMC) e quitosana (Qs), suportados em redes de poli (ácido metacrílico)-co-poliacrilamida (PMAA-co-PAAm). Também foi investigada a influência da zeólita nas principais propriedades agroquímicas desses materiais como sorção e dessorção de herbicidas. A estabilidade da zeólita na solução polimérica foi estudada por meio de medidas de viscosidade. Estes comprovaram que a adição de polissacarídeo na solução formadora dos hidrogéis possibilita a obtenção de um hidrogel nanocompósito homogêneo. A incorporação da zeólita nos hidrogéis foi confirmada pela presença das bandas características da zeólita em 798 cm-1 e 600 cm-1 nos espectros de FTIR dos hidrogéis nanoestruturados. Outros indícios de incorporação foram a redução no volume dos poros e a presença de microporos nas paredes dos poros dos hidrogéis, aumento na massa residual dos hidrogéis nanoestruturados a 800ºC, observados nos resultados obtidos por microscopia eletrônica de varredura (MEV) e análise termogravimétrica (TG), respectivamente. Constatou-se também que a presença da zeólita reduziu o grau de intumescimento desses materiais, devido ao decréscimo na elasticidade das cadeias poliméricas. Entretanto, nos resultados de dessorção observou-se que a presença da zeólita pode... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In order to apply agrochemicals in a controlled manner, and to reduce the damages to the health and environmental caused by these, two new hydrogels based on carboxymethylcellulose (CMC) and chitosan (Qs) polysaccharides supported on poly(methacrylic acid)-co-polyacrylamide (PMAA-co-PAAm) networks were synthesized. The influence of zeolite on the main properties of these materials such as sorption and desorption was also investigated. The stability of zeolite in the polymeric solution was studied by viscosimetry. These results showed that the addition of polysaccharide in the hydrogel-forming solution enables the obtaining of homogeneous nanocomposite hydrogels. The incorporation of zeolite into hydrogels was confirmed by the presence of spectroscopic bands at 798 cm-1 and 600 cm-1 in the FTIR nanocomposite spectra. Other indicatives were the reduction in pore volume and the presence of micropores in the pore walls of zeolite hydrogels, and increase in the residual mass of nanostructured hydrogels at 800ºC, observed by scanning electron microscopy (SEM) and thermogravimetric analysis (TG), respectively. It was also observed that the presence of zeolite reduced the degree of swelling of these materials, due to the decrease in the elasticity of the polymeric chains. The results of desorption in saline medium show that the hydrogels studied in this work can reduce the presence of Al+3 ions, which in acidic soils are harmful to some crops. These results indicate that the hydrogel... (Complete abstract click electronic access below) / Doutor

Presented work is focused on the deposition and characterization of thin and ultrathin plasma polymer films, then also on the preparation of nanocomposites metal/plasma polymer. The characterization of plasma polymer films was partly done in-situ without exposing the samples to the atmosphere. The thickness of prepared films was measured by spectral ellipsometry, the chemical composition was measured by XPS. The morphology and optical properties of deposited films were measured ex-situ. It is shown that during the initial stages of growth the properties of plasma polymer films depend on their thickness and also on the material of the substrate. Many interesting applications were explored for prepared nanocomposites metal/plasma polymer. They can be used as superhydrophobic coatings, gradient coatings, substrates for Raman spectroscopy or as antibacterial coatings. Moreover, special optical properties of prepared nanocomposites were studied in detail. Presented work has an experimental character.

Philosophiae Doctor - PhD / The application of porous materials into industrial hydrogen (H2) storage systems is based on their use in combination with high-pressure cylinders. The processing of metal-organic frameworks (MOF) powders into shaped forms is therefore imperative in order to counteract the adverse effects of poor packing of powders in cylinders. The fabrication of shaped MOFs has, however, been shown to be accompanied by compromised properties such as surface areas, gravimetric and volumetric H2 capacities, and also the working/deliverable H2 capacities in comparison to MOF powders.