La recherche présentée dans cette thèse traite de la synthèse, propriétés et applications optoélectroniques de matériaux nanohybrides basés sur le greffage d’une porphyrine donneur d’électron et d’un dérivé du fullerène sur des nanoparticules de ZnO.Ces molécules sont accrochées à la surface de l’oxyde métallique grâce à une fonction acide carboxylique. L'effet du rapport molaire porphyrine / fullerène, de la polarité du solvant et la forme des nanoparticules sur les propriétés optiques des nanohybrides ont été étudiés. Les interactions porphyrine / fullerène à l’échelle moléculaire apparaissent pour un rapport de 1:2 à l'état co-greffé sur des nanobâtonnets de ZnO. Cela est indiqué par le fort décalage bathochrome du pic de Soret des porphyrines et de l’extinction de sonémission de fluorescence. Toutefois, à cette valeur du rapport, le complexe de transfert de charge n'est pas détectable. La formation de ce complexe requiert à la fois les molécules donneur et accepteur d’électron d'être d’être maintenues à proximité, ce qui est réalisableen augmentant le rapport stoechiométrique à 1:3 et au-delà. Dans l’acétonitrile, une bande d’absorption de transfert de charge de faible intensité apparaît vers 700-800 nm, ainsi qu’une bande d'émission à 800 nm, caractérisant la complexation supramoléculaire à la surface de l’oxyde métallique. Lorsqu'ils sont utilisés pour la fabrication de la couche active dans une cellule solaire à hétérojonction hybride, les nanobâtonnets de ZnO fonctionnalisés montrent une efficacité de conversion lumineuse pour des valeurs faibles du rapport porphyrine / fullerène, mais l’augmentation du taux de fullerène tend à diminuer le rendement de conversion photovoltaïque. Cet effet a été relié à l’apparition de défauts morphologiques dans les films minces induite par l’agrégation des nanotubeslié au taux et rapport de greffage des molécules organiques. / The research presented in this dissertation deals with the synthesis, properties andoptoelectronic applications of the nanohybrids based on dye and fullerene functionalizedZnO nanoparticles. These molecules being acid functionalized, were co-grafted on thesurface of ZnO nanoparticles. The effect of changing ratio of donor to acceptor, polarityof the solvent and shapes of the nanoparticles on porphyrin/fullerene interaction werestudied. The molecules were found appreciably interacting at a ratio of 1:2 under the cograftedstate on ZnO nanorods. This was indicated by the strong bathochromic shift of thesoret peak of porphyrin and quenching of its fluorescence however, at this ratio chargetransfer complex is not detectable. The complex formation requires both the donors andacceptors to be enough close to each other to undergo Van der Waal’s type interactionwhich is achievable by raising the stoichiometric ratio to 1:3 and beyond. Weak CTabsorption (700-800 nm) and emission bands (800 nm) characterizing supramolecularcomplexation, were noticed only in polar solvent acetonitrile. When applied as acomponent of the active layer in bulk heterojunction hybrid solar cells, the dyefunctionalized ZnO nanoprods raised the efficiency of the solar cells at lowconcentrations but addition of fullerene had an inverse effect. This was investigated to bedue to the morphological defects induced by the clusterization of nanorods.

The pi-electron oligomers: Their synthesis and properties This diploma thesis is focused on the synthesis of p-oligophenyleneethynylene rods (dimer and trimer) containing laterally attached naphtalenediimide units as electron acceptor groups. These functionalised short oligomers are intended to serve as model oligodentate acceptors in the study on multiple interactions with electron rich molecules. The oligomers were assembled from building blocks such as aryl iodides and aryl alkynes bearing a naphthalenediimide unit. The functionalised monomers were combined in a stepwise way by using Sonogashira reaction to form the target p-oligophenyleneethynylene oligomers. The introductory UV-VIS spectroscopic studies on charge transfer complexes between electron donor (pyrene) and electron acceptor (a naphthalenediimide derivative) were performed. In addition, multiple noncovalent interaction between the electron acceptor dimer containing two naphthalenedimide moieties and the electron donor dimer containing two pyrene moieties were investigated by using 1 H NMR titration. The resulting oligomers and their precursors were characterized by using 1 H NMR, 13 C NMR, MS and IR spectroscopy.

No description available.

There is big interest in cheap, sensitive and selective gas sensors. In this work, substituted soluble phthalocyanines are proposed as a sensing materials for several gases. Optical, electrical and gas sensing properties of several phthalocyanines were studied and the mechanisms of their interaction with several analyte gases are described. It was found, that sulfo-substituted Pcs has good sensitivity to humidity. Sulfonamide-substituted phthalocyanines are promising for nitrogen dioxide and volatile organic compounds detection. tert-Butyl-substituted phthalocyanines are sensitive to NO2 under higher temperature and seems to be used for environmental monitoring. Commercial gas sensors for NO2, ethanol and humidity were successfully created.

No description available.

(Doctoral Thesis, 2016, Mgr. Tomáš Faukner, IONIC POLYACETYLENE TYPE POLYMERS AND POLYMER NETWORKS BY CATALYST FREE QUATERNIZATION POLYMERIZATION) The composition and structure of a series of ionic π-conjugated poly(monosubstituted acetylene)s prepared via catalyst-free quaternization polymerization (QP) of 2-ethynylpyridine (2EP) activated with equimolar amount of alkyl halide [RX = ethyl bromide, ethyl iodide, nonyl bromide and haxadecyl (cetyl) bromide] as a quaternizing agent (QA) have been studied in detail. The performed QPs gave ionic polymers well soluble in polar solvents, with approximately half of pyridine rings quaternized, which implies that also non-quaternized monomers were involved in the process of QP. The configurational structure of polyacetylene main chains was suggested based on 1 H NMR, IR as well as Raman (SERS) spectral methods. The QPs in bulk gave more expected irregular cis/trans polymers while the QPs in acetonitrile solution gave high-cis polymers. A series of prepared symmetrical bi-pyridylacetylene based monomers has been polymerized via QP approach resulting into a series of new ionic π-conjugated poly(disubstituted acetylene) type materials. It is therefore obvious that the mechanism of quaternization activation frequently applied on monosubstituted...