SURFACE MODIFICATION OF POLYCRYSTALLINE ALUMINUM SUBSTRATE IN SOLUTION CONTAINING TETRAPHENYLBORATE ANION

The effect of tetraphenylborate anions on the oxidation/reduction cycl ing behaviour of poly-crystalline aluminium surfaces in 0.1 M NaClO4 s olutions in the context of elimination of passive oxide formation, rou ghening and faceting is examined. Surface area enhancement without pas sive film formation was revealed by the i-t transients and impedance s pectra of untreated and treated electrodes. Scanning Electron Microsco pe studies show evidence for crystallite formation upon treatment. X-r ay diffraction measurements revealed preferential orientation of pc-al uminium in the (111) direction.