MORPHOLOGICAL INVESTIGATIONS OF ELECTROCHEMICALLY DEPOSITED POLYANILINE FILMS

The effect of rate of mass transfer on the surface morphology of elect rochemically deposited polyaniline films was studied using scanning el ectron microscopy (SEM). The rate of mass transfer was controlled by v arying the sheet resistance of electrode and the monomer concentration . Both these parameters are found to affect the deposition process and the surface morphology to a considerable extent. The polyaniline film deposited using 0.1 M monomer concentration on electrode with 50 Omeg a/square sheet resistance shows a granular structure joined together w ith fine fibrils. Increase in the monomer concentration and decrease i n the sheet resistance of the electrode lead to the enhancement in the growth of the polymer film as revealed from the current time transien t measurements. The formation of fibres with different shapes such as rope-like, curved, cyclone-like, petal-like, wavy, wing-like, and cris s-cross linking depends on the growth conditions of films. The sheet r esistance of electrode mainly determines the number density of these f ibres, whereas, the patterning is governed by the monomer concentratio n.