Abstract
A metastable phase ITO/VO2(B) film was prepared under the optimum conditions using a cyclic potentiometric device. Then, a monoclinic phase ITO/VO2(M) film was prepared from the ITO/VO2(B) film using annealing temperatures from 550 to 750 degrees C. From the XRD analysis, the crystallinity increases with the annealing temperature from 550 to 750 degrees C. The ITO/VO2(M) film annealed at 750 degrees C had the optimum optical and structural properties. Then, three electrodes of ITO/VO2(M)/Au were prepared: electrode (I), electrode (II), and electrode (III) at annealing temperatures of 550, 650, and 750 degrees C, respectively. The three electrodes were applied to generate hydrogen from H2O and examined using the current-volt (I-V) relationship. Additionally, the incident photon-to-current conversion efficiency (IPCE) under monochromatic illumination was investigated. The electrode showed 4% efficiency at 25 degrees C and reached 8.1% at 45 degrees C. Finally, the different thermodynamic parameters, i.e., activation energy (E-a) enthalpy (Delta H*), and entropy (S*), were determined for electrode (III) to be 27.33 kJ mol(-1), 124.93 kJmol(-1), and 109.66 JKmol(-1), respectively.