Title:
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Structural and morphological aspects of templated non-planar phthalocyanines
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Metal phthalocyanines prepared as single crystals and thin films have been analysed using a combination of microscopy and diffraction based characterisation. Vanadyl phthalocyanine (VOPc) and chloroaluminium phthalocyanine (ClAlPc) prepared as thin films on oxidised silicon at a variety of substrate temperatures are analysed by atomic force microscopy (AFM) and x-ray diffraction (XRD). Elevated substrate temperatures are found to promote larger morphological features and out-of-plane diffraction. In addition single crystals of VOPc are grown and the single crystal structure is re-determined. Thin films of copper iodide (CuI) are prepared, at a variety of substrate temperatures, and analysed using AFM and XRD. These films are found to be (111) oriented and are used as structural templating layers for sequential growth of VOPc and ClAlPc thin films. These structural templates are found to alter the structure of thin films of VOPc and ClAlP. VOPc is shown to adopt three distinct molecular orientations whereas ClAlPc is found to adopt only one. In addition to this the growth behaviours of VOPc and ClAlPc on thin films of CuI is explored using AFM and different growth modes are suggested. Single crystals of CuI are synthesised from solution for use as a model structural templating system and characterised using low energy electron diffraction (LEED), AFM and XRD. These crystals were oriented to their (111) face and subsequently used as a model template for the growth of VOPc. The films of VOPc are analysed using XRD and AFM and the (111) surface is found to promote one orientation of VOPc, suggesting that the molecules interact differently with a single crystal surface than with a polycrystalline thin film. Zn- and O-terminated (0001) Zinc Oxide (ZnO) crystals are prepared and used to investigate the effects of surface chemical termination on the growth of VOPc thin films. The ZnO surfaces are analysed using LEED, XRD and AFM and are found to adopt different surface reconstructions under identical preparation conditions. These surface reconstructions result in VOPc films which have different structures and morphologies.
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