| dc.description.abstract | Renewable energy correlated to hydrogen utilization has been considered as one of potential solutions to solve nowadays urgent issues that humankind encountered in energy crisis and global warming. Photoelectrochemical (PEC) water splitting was a promising method to convert the solar energy into hydrogen by Honda and Fujishima in 1972. In this study, nanostructured α-Fe2O3 have been fabricated on fluorine-doped SnO2 (FTO) glass substrate by DC magnetron sputtering process using a simple, cheap and rapdily method of electrochemical anodization and considered to replace TiO2 for PEC water splitting application. Influences of anodized parameters (i.e., anodization temperature and anodization time) and re-annealed treatment on structural, optical, anti-corrosion and PEC characteristics have been investigated. The as-obtained samples after annealing at 550 ℃ for 2 h in air ambient were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra, UV-visible spectra and electrochemical analysis. After annealing, all samples revealed only hematite signals by Raman spectra and XRD pattern. Result from SEM, different etching temperatures show various morphologies, i.e., thin film at 20 ℃, nanoparticles at 40 ℃ and nanorods at 60 ℃. However, high anodizing temperature (80 ℃) would lead a great fraction of FTO surface exposed and therefore compromises the photocatalytic activity of hematite electrodes. In PEC results, the α-Fe2O3 nanorods had a better performance of 0.59 mA/cm2 at 0.6 V vs. SCE compare to other nano-structures due to a suitable thickness (330 nm), higher absoprtion in visible wavelength and a higher intensity of (110) peak in XRD pattern. On the other hand, the α-Fe2O3 nanorods diameter increased ranging from 300 to 1500 nm with increasing re-annealed temperature ranging from 600 to 800 ℃ for 20 min, respectively. Based upon our observations, the α-Fe2O3 nanorods re-annealed at 750 ℃ for 20 min indicated a better PEC response with photocurrent density of about 1.50 mA/cm2 at 0.6 V vs. SCE. This value was about 2.54 times higher than the simply annealed at 550 ℃ for 1 h. Observed higher photocurrent density was attributed to Sn-doped on the surface of hematite through its diffusion from the FTO substrate in the re-annealing duration althougth the I(110)/I(104) of samples decreased from 1.53 to 0.80 with re-annealed temperature up to 750 ℃. | en_US |