Copper-based hierarchical micro/nanostructures were prepared using a novel electrochemical route on polypyrrole−polystyrene sulfonate (PPy−PSS) thin films. The resulting structures are composed of copper hydroxysulfates, as confirmed by the electrochemical, spectroscopic, and X-ray diffraction characterization. The electrochemistry of the film is a key factor in the overall deposition of the micro/nanostructures. The PPy−PSS films capture cations from the copper sulfate electrolyte solution and facilitate the reduction of dissolved oxygen to hydroxide ions. The system then acts like a nanoreactor as the Cu2+ and OH− ions are concentrated on the polymer surface, which in the presence of the SO4 2− ions from the electrolyte solution results in the electrocrystallization of the copper hydroxysulfates hierarchical structures.

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TEM analysis of mesoporous materials is generally undertaken to give qualitative results. Accurate quantitative analysis is demonstrated in this study. A systematic image analysis of a powder form of a hexagonal mesoporous material known as KIT-6 is conducted using a transmission electron microscope (TEM). Three types of image contrast typically appear in this material (a hexagonal honeycomb structure, wide and narrow parallel lines). The honeycomb face is used to characterise this material in terms of a conventional 2-D hexagonal structure and the d-spacings for the (100) and (110) planes are experimentally measured in varying focus conditions. A tilting experiment is conducted to determine how the angle of tilt affects the line spacing and their visibility. Tilting has very little effect on the line spacing, whereas it affects the visibility of both the wide and narrow lines by limiting an angle range of visibility. The hexagonal lattice structure parameter determined by TEM method is found to be approximately 7% lower than that calculated by low-angle X-ray diffraction. Thus we conclude that TEM data can be used to determine the geometry and dimensions of hexagonal mesoporous silica materials, with a small error in the hexagonal lattice parameter.

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