Effects of H2SO4 Content on Electrochemical Activation of Etched Tunnels on Aluminum Foil

Electrochemical behavior of aluminum foil in H2SO4 solutions was intensively studied. Because of the antagonistic effect of and H+ contained in H2SO4, the surface etching of the aluminum foil in the H2SO4 solution gradually increased with the H2SO4 concentration. When HCl was added to the H2SO4 solution, the surface etching of the aluminum foil became dependent on the H2SO4 concentration. The increased H2SO4 concentration reduced the pitting resistance of the aluminum foil, thus improving the distribution uniformity of the etched tunnels. The decreased tunnel length was analyzed by using an electrochemical process.