Electrochemistry and spectroelectrochemistry of perrhenates in sulfuric acid solutions

The spectroscopic and electrochemical behavior of perrhenate ions was examined in aqueous solutions containing concentrated sulfuric acid. The chronopotentiometric results show a multi-electron reduction process. Additional hydrodynamic experiments reveal generation of an ionic form of Re(V) that undergoes oxidation on the ring electrodes. Reduced rhenium species are transformed in 12 M H2SO4 into soluble species characterized by an absorption band at 366 nm.