Tetrahexylammonium bromide is widely used as a phase transfer catalyst in organic synthesis. It facilitates the transfer of reactants between immiscible phases, enhancing reaction rates and yields in processes like nucleophilic substitution, oxidation, and reduction. It is also employed in the preparation of ionic liquids and as a surfactant in various industrial applications. Additionally, it plays a role in electrochemical studies and in the synthesis of nanoparticles, where it helps stabilize and control particle size. Its ability to modify interfacial properties makes it valuable in materials science and nanotechnology.