Mica substrates decorated with a periodic array of gold squares are used to guide the growth of two-dimensional colloidal crystals of charged polystyrene particles. For polystyrene spheres (500 nm in diameter) suspended water, with a dilute surfactant (5 mM sodium dodecylsulphate (SDS)) in the colloidal suspension, the self-assembly process leads to the formation of ordered colloidal monolayers nearly exclusively on gold, confined laterally by the boundaries of the prefabricated gold terraces. This method provides an efficient route to guided growth of novel colloidal monolayers, with potential applications in, e.g., bio-sensing and photonics.
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