Photo(electro)catalytic Activity of Cu2+-Modified TiO2 Nanorod Array Thin Films under Visible Light Irradiation

Abstract

In the present study, a two-step method was applied to synthesise Cu2 þ -modi?ed TiO2 nanorod array

thin ?lms for photocatalytic processes. TiO2 nanorod array thin ?lms were synthesised by a

hydrothermal method and then modi?ed with an ultrasonic-assisted sequential cation adsorption

method. The samples were characterised by X-ray diffraction (XRD), UV–vis diffuse re?ectance

spectra (DRS), scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy and

inductively coupled plasma mass spectro- scopy (ICP-MS) analysis. The photoelectrochemical

properties of the samples were evaluated by linear sweep voltammetry and Mott–Schottky analysis;

photocatalytic activities were tested by methylene blue degradation under visible light. The

photocurrent density of the TiO2/FTO sample modi?ed with 50 mM Cu2 þ solution was 26 times higher

than that of the unmodi?ed TiO2/FTO sample. Additionally, methylene blue degradation ef?ciency

under visible light was increased 40% with respect to the ef?ciency of the unmodi?ed sample. The

mechanism of the photocatalytic activity enhancement of Cu2 þ -modi?ed TiO2

lms was discussed.