Tunable electrochemical properties of liquid phase deposited TiO2 films

Abstract

Titanium dioxide (TiO2) films on glassy carbon (GC) electrode surface were prepared by the liquid phase deposition (LPD) process for different deposition times. The morphological structure, interfacial property and electrocatalytic activity of as-prepared LPD TiO2 films on GC surface were studied by field-emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The FE-SEM observation showed that the deposition time controlled the morphology of film on GC surface. With increasing deposition time, TiO2 formed nanoparticles at the initial 5-h stage and compact thick films after 20 h. Due to the semiconducting properties of TiO2, the LPD films inhibited the electron transfer process of [Fe(CN)6]3−/[Fe(CN)6]4− on GC by increasing the redox reaction peak potential separation of CV curve and electron transfer resistance of EIS. The inhibition was increased with TiO2 film thickness. Nevertheless, the onset reduction potential of maleic acid decreased with increasing LPD TiO2 film thickness while the cathodic and anodic currents increased, demonstrating the useful electrocatalytic activity of LPD TiO2 films.