Photoelectochemical behavior of TiO2-NT’s modified with SILAR deposited iron oxide

• α-Fe2O3 is obtained via fast forced hydrolysis in hypochlorite solution at room temperature.
• α-Fe2O3 is deposidetd on TiO2-NT’s using SILAR.
• Better anodic photoelectechemical behavior is obtained.
• Flat band potentials and band gaps are determined.
• The plausible mechanism is proposed.

The fast reaction of forced hydrolysis of iron(III) nitrate in hypochlorite solution at room temperature, leads to the formation of mainly hematite, α-Fe2O3. Successive ion adsorption and reaction (SILAR) is applied to decorate an electrochemically formed TiO2 nanotube electrode. The anodic photoelectrochemical behavior of pure TiO2-NT’s and modified electrodes are investigated in a sulfate containing solution at pH = 9.2. It is shown that such a modification leads to an increase of anodic photoactivity, as well as that at the same current density, the photoelectrochemical cell with a modified electrode operates at a voltage lower by 0.7 V. The band gap and flat band potentials are estimated, and the structure of the band gap and possible charge transfer reactions and mechanism are discussed.