Chemical and electrochemical deposition of conducting polyaniline on lead

Chemical and electrochemical deposition of polyaniline (PANi) on lead from aqueous electrolytes has been carried out. PbO2 is used for chemical deposition. Pb is anodizing in a favorite condition, potentiostatically, until PbO2 is produced. The produced PbO2 has been used as oxidant, which oxidized aniline and deposited chemically produced PANi films on lead. The chemically produced PANi acts as a passive layer and protects the substrate from dissolution during anodic polarization. Its quality is as high as electrochemically synthesized one. The chemically deposited PANi can be used for the electrodeposition of PANi films by convenient methods. In this procedure, 1M H2SO4 should be used as supporting electrolyte to achieve suitable results. Since, PbO2 as oxidant has the highest reduction capacity in this concentration, the produced PANi has the best quality and also SO42− is the best counter ion for the synthesis of PANi. Lead oxidation does not occur during electrochemical deposition of PANi. This is a modified electrode on an inexpensive metal which can resists corrosion by a coated PANi film. The films show good electroactivity in acidic electrolytes similar to that of the PANi deposited on platinum, which indicates that the underlying oxidizable metal is fully protected. Among the electrochemical methods, galvanostatic deposition has given the best results. Very adherent thickness-controlled PANi films were obtained by this method.