SYNTHESIS OF RUTILE-TiO2 NANOROD ARRAYS FOR EFFICIENT SOLAR WATER SPLITTING VIA MICROWAVE-ASSISTED HYDROTHERMAL METHOD

Abstract

Using a microwave-assisted hydro thermal method (MWAHM) a single crystalline of vertically aligned TiO2 nanorod (NR) arrays has been achieved via the novel ultra-rapid synthetic method for the production. High-quality NR arrays with controlled film thickness were achieved with fine control of the growth conditions as well. The effect of the different reaction conditions of MWAHM such as reaction time and growth temperature on the morphology, crystal orientation, and photo catalytic activity have been systematically investigated. In a typical condition of the MWAHM using 0.4 cm3 of titanium(IV) n-butoxide (TBO) at 180 °C for 40 minutes, a small diameter of 124 nm and short length 2.93 µm of TiO2 nanorods, are grown on fluorine-doped tin oxide (FTO) substrate. However, the photo current density produced TiO2 NRs of 2.90 mA cm-2 with a maximum photo conversion efficiency of about 2.7% which confers excellent photoelectrochemical performance. In comparison with the typical hydro thermal method (HM) synthesized NRs, the ultra-fast MWAHM synthesized NRs offers five times more efficiency photoelectrochemical (PEC) water splitting than the hydro thermal method (HM). The results suggest that these dense and aligned one-dimensional TiO2 nanorods are promising for hydrogen generation from water splitting based on PEC cells.