Dealloying of PdNi5 Alloy in 1.0M Nitric Acid

Abstract

Binary palladium alloys with nickel are known to have catalytic activity and are also used as catalyst-trap in the synthesis of nitric acid. High Pd alloys are corrosive resistant in many solutions, including highly alkaline and highly acidic. Although generally not prone to corrosion in low concentrations of mineral acids due to the high content of palladium in it, this alloy is still prone to the dealloying effect under specific conditions. The dealloying process was researched under anodic polarization in 1.0M nitric acid solution. Scanning electronic microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and electrochemical methods were used to study the susceptibility of PdNi5 alloy to dealloying.