Influence of growth time on photoelectrical characteristics and photocatalytic hydrogen production of decorated Fe_2O_3 on TiO_2 nanorod in photoelectrochemical cell

摘要

We developed decorated Fe2O3 on the surface of one dimensional (1D) TiO2 nanorods (NRs) as a photocatalyst in a photoelectrochemical hydrogen production system using the two-step hydrothermal technique. The photocatalytic hydrogen production over the designed 1D TiO2@Fe2O3 NRs was optimized by varying the hydrothermal duration. Several characterization techniques were applied to study the physicochemical and photoelectrochemical properties of the prepared photocatalysts. It was observed that the adhesiveness and electrical connection of the TiO2@Fe2O3 and FTO substrate, crystal growth, and photoelectrochemical behavior strongly depend on the hydrothermal duration time. The photoanode with a growth time of 24 h produced the maximum amount of hydrogen (640 mu mol cm(-2)) under visible light with external potential from dye-sensitized solar cells in 1 M KOH and 5 vol% glycerol solution in the photoelectrochemical cell. The EIS data showed that this photocatalyst had the lowest charge transfer resistance of 167.84 Omega and the longest electron lifetime of 347.97 ms. Also, its Mott-Schottky data revealed a more negative flat bad potential of -1.1 V with profound ability of proton (H+) reduction to H-2 and high donor density of 3.55 x 10(21) cm(-3), which resulted in much more photocurrent density and photoconversion efficiency at the electrode/electrolyte interface compared to others.