Effects of hydrothermal temperature on the morphology and photoelectrocatalytic performance of TiO2-based nanomaterials photoelectrode

Abstract

TiO 2-based nanomaterials (BNMs) photoelectrode was successfully synthesized via a facile and controllable hydrothermal procedure. The as-prepared TiO 2-BNMs photoelectrode was characterized by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The resulting TiO 2-BNMs samples assembled by different morphologies were obtained through changing hydrothermal temperature that were: (i) One-dimensional (relative to nanosheets) nanobelts at 140°C, (ii) two-dimensional nanosheets at 160–180°C and (iii) three-dimensional network nanowires at 200–220°C. Structural investigation of the obtained nanomaterials revealed that the content of anatase increased as increasing the apparent dimensionality of the materials. The photoelectrochemical performance of TiO 2-BNMs photoelectrode was elucidated by comparative investigation on the electron transport and electron–hole (e-/h+) recombination in TiO 2-BNMs sample with typically morphology. The photoelectrochemical performance of the TiO 2-BNMs sample was obviously dependent on the morphology. Compared to the nanobelts and the network nanowires structure, the two-dimensional nanosheets displayed the more effective photogenerated electron transfer and reduced electron–hole recombination rate. Moreover, two-dimensional nanosheets had significantly enhanced photoelectrocatalytic efficiency for degradation of methyl orange (MO).