ELECTROCHEMICAL GENERATION OF 2-DIMENSIONAL SILVER PARTICULATE FILMS AT MONOLAYER SURFACES AND THEIR CHARACTERIZATION ON SOLID SUBSTRATES

Electrochemical reduction of silver ions at the interfaces of monolayers prepared from arachidic acid (1) and dialkyl polymenzable phosphate surfactants 2 and 3 resulted in the two-dimensional formation of uniform films which consisted of interconnecting, 250 Å diameter, roughened silver particles. No formation of silver particles could be observed in the absence of monolayers or at monolayer interfaces prepared from positively charged dioctadecyldimethylammonium bromide (4) and polymerizable dialkylammonium chloride surfactant (5). The silver particulate films were transferred on quartz, highly oriented graphite, and celluloid-coated copper grids as substrates. Absorption spectra of the silver particulate film on quartz indicated an mterband transition at 321 nm and an absorption maximum at 387 nm. Scanning tunneling microscopy of the silver particulate film on graphite revealed the presence of interconnecting particles with heights of 100-200 Å and average short and long axes of 200 and 300 Å, respectively. Electron diffraction rings of the silver particulate film on a grid were analyzed for a face-centered cubic polycrystalline structure with a unit lattice constant of 4.08 Å. Resistivity of the silver particulate film on quartz was determined to be 4.5 × 10-4 Ω cm. © 1990 American Chemical Society.