TiO_2 nanorods grown by hydrothermal method and their photocatalytic activity for hydrogen production

摘要

TiO2 nanorods were prepared by hydrothermal method over TiO2 seed layers deposited by DC Sputtering. From the XRD structural characterization, it has been stated that TiO2 seed layer present mainly the anatase phase with some contributions of rutile phase, while for TiO2 nanorods, the rutile phase is present. The thin film thickness were measured using a profilometer, resulting in a thickness of 310 nm for the seed layer and similar to 400 nm for TiO2 nanorods. PL analysis for both films presented an indirect transitions Gamma(1b) - X-2a, as well as oxygen vacancies, defects and surface states. Photocatalytic H-2 production for TiO2 seed layer film was around 38 mu mol, while TiO2 nanorods produced 132 mu mol. This is attributed to the increase to the midgap states present below the conduction band and near to the valence band, which help to improve the photocatalytic activity. (C) 2018 Elsevier B.V. All rights reserved.