Rapid, microwave-assisted deposition of anisotropic silver nanostructures on various substrates

A facile, rapid, and scalable in situ microwave-assisted solvothermal technique (MAST) has been developed to deposit anisotropic silver nanoparticles (AgNP) on various substrates in a solution medium. SEM-EDS and XRD were used to characterize the morphology and structure of the deposits. Deposition on non-patterned aluminium led to near-spherical AgNP agglomerates all across the surface. Deposition on the glass at optimum solution concentration led to mirror-like coatings comprising spherical ∼50 nm particles, whereas no coating occurred at lower concentrations. AgNPs decorated the hexagonal pattern formed on a nano-patterned aluminium (NPA) substrate. Among various precursor concentrations used for deposition on NPA, the 10 μM concentration resulted in conformal deposition, with nanoparticles decorating the hexagons in NPA. In contrast, AgNP density was lower in the concave dimples on NPA. Our work demonstrates a quick and easy approach for the AgNPs' deposition, with control over size, and morphology. It can be used for deposition on large substrates, potentially making it suitable for surface-enhanced spectroscopic applications.