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Covalently linked Au-NPs micropatterns have been successfully fabricated from the self-assembly film composed of 4-mercaptophenol-capped Au nanoparticles (Au-NPs) and -N2+ containing polymers of nitro-diazoresin (NDR) by selective exposure to UV light and development in sodium dodecyl sulfate (SDS) aqueous solution. The resultant well-defined micropatterns were characterized with AFM and XPS.

NiFe(2)O(4) multi-particle-chain nanofibres have been successfully fabricated using electrospinning followed by calcination, and their morphology, chemistry and crystal structure were characterized at the nanoscale. Individual NiFe(2)O(4) nanofibres were found to consist of many nanocrystallites stacked along the nanofibre axis. Chemical analysis shows that the atomic ratio of Ni : Fe is 1 : 2, indicating that the composition was NiFe(2)O(4). The crystal structure of individual NiFe(2)O(4) multi-particle-chain nanofibres proved to be polycrystalline with a face centered cubic (fcc) structure. The nanocrystallites in the nanofibres were revealed to have a single-crystal structure with random crystallographic orientations. The magnetic measurements reveal that the NiFe(2)O(4) multi-particle-chain nanofibres have a coercivity force of 166 Oe. A "chain of sheets" micromagentism model was proposed to interpret the observed magnetic behaviour of the NiFe(2)O(4) multi-particle-chain nanofibres. Simulation studies of the coercivity are in good agreement with the experimental results at room temperature. It is believed that this work will significantly expand the use and application of these compounds in the field of biomagnetic nano-devices and improve understanding of the magnetic origin of spinel ferrites.

Stable, ultrathin micropatterns containing CdS nanoparticles (CdS‐NPs) were fabricated in a two‐step process. In the first step, a precursor film was built‐up by the layer‐by‐layer electrostatic self‐assembly of photosensitive nitro‐diazoresin and mercaptoacetic acid capped CdS nanoparticles. In the second step, the film was selectively exposed to UV light through a photomask and developed in an aqueous solution of sodium dodecylsulfate (SDS). The formation of covalently linked micropatterns was based on the different solubilities of the irradiated and non‐irradiated parts of the film in the developer. Namely, the irradiated regions were cross‐linked and insoluble, whereas the non‐irradiated regions, linked with ionic bonds, were removed by the SDS solution. The resultant patterns were systematically characterized with atomic force microscopy, field emission scanning electron microscopy, optical microscopy, and X‐ray photoelectron spectroscopy.

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