Search for multi-functional catalysts: The electrooxidation of acetaldehyde on Platinum-Ruthenium-Rhodium electrodeposits

► Acetaldehyde electrooxidation depends on the composition of PtRuRh electrodeposits. ► The best activity of PtRuRh does not correspond to an expressive CO2 production. ► CO2 production on Rh is a minor component of the global charge. ► Rh inhibits the formation of acetic acid. ► Consequently, the global catalytic activity is lowered on Rh rich surfaces.