Tetrabutylammonium perrhenate is primarily used as a catalyst in organic synthesis, particularly in oxidation reactions. It facilitates the transfer of oxygen atoms, making it valuable in the oxidation of alcohols to aldehydes or ketones. Additionally, it is employed in the preparation of rhenium-based complexes, which are useful in various catalytic processes. Its role in electrochemical applications is also notable, where it serves as an electrolyte additive to improve conductivity and stability in certain systems. Furthermore, it finds use in research and development for studying reaction mechanisms involving rhenium compounds.