The surface morphology of the IO-TiO2 electrodes was studied by field emission scanning electron microscope imaging (TESCAN MIRA3 FEG-SEM) at an electron beam accelerating voltage of 5 kV (In-beam Secondary Electron detector). The roughness factor was determined by an organic dye adsorption experiment adapted from that for nanostructured metal oxide electrodes . The dye has been shown to form a monolayer on the electrode surface. An IO-TiO2 electrode with a defined geometrical area of 0.19 cm 2 was first immersed in a 1.5 mM aqueous solution of Orange II for 30 minutes. The adsorbed Orange II dye molecules were then desorbed in 1 M NaOH (3 mL) and the amount was quantified using a UV-Visible spectrophotometer (Agilent Cary 60) through the construction of a calibration curve with known concentrations (1.5 µM, 3 µM and 6 µM). Calculations assumed that each Orange II dye molecule occupied an area of 0.4 nm 2 .