Electrochemical properties of Ti/(Ru0.3Ti0.7)O2 anodes: The influence of the anion chain in butylammonium-based ionic liquids

Ionic liquids (ILs) are promising solvents for preparing highly conductive and corrosion-resistant mixed metal oxide (MMO) electrodes used as anodes in electrolysis. There were synthesized dibutylammonium acetate [DBA] [Ac], dibutylammonium propionate [DBA] [Pr], and dibutylammonium butyrate [DBA] [Bu], not previously studied for MMO synthesis using titanium substrates, aiming to investigate the influence of different sizes of anions on the properties of DBA ILs and the resulting Ti/(Ru0.3Ti0.7)O2 MMO electrodes. Each IL was characterized by pH, viscosity, nuclear magnetic resonance spectra (NMR), transform infrared spectrum (FTIR), thermogravimetric analysis (TGA-DTG), and electrochemical impedance spectroscopy (EIS). The MMO electrodes were studied through Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX), X-ray Photoelectron Spectroscopy (XPS), Cyclic Voltammetry (CV), and EIS. The electrochemical properties of Ti/ (Ru0.3Ti0.7)O2 anodes were investigated in cyclic voltammetry, EIS, and accelerated service lifespan tests under highly oxidizing conditions. Larger anionic chains led to more capacitive and efficient electrodes with the highest morphology factors. The MMO anodes developed exhibit superior voltammetric charge and enhanced stability over other MMO anodes with the same composition prepared with alternative ionic liquids. Thus, this study could advance the understanding of ILs in MMO electrode synthesis to develop high-performance electrodes for diverse electrochemical systems.