Effect of TiO2 nanorod thickness on optical properties of Ba0.8Sr0.2TiO3 film via hydrothermal method

Hydrothermally produced perovskite-type barium strontium titanate Ba 0.8 Sr 0.2 TiO 3 (BST) nanorods deposited on TiO 2 substrate for 2 h at 160 °C. The TiO 2 nanorods prepared using hydrothermal method with varying reaction time from 4 to 30 h. X-ray diffraction (XRD) was used to analyze the phase compositions and lattice characteristics of the films. The absence of peaks from TiO 2 in the XRD spectra of BST indicates that the films have been entirely transferred. The films have a thickness of 1.92–3.96 μm and an average diameter of 40.36 nm according to FESEM pictures. The particles have a relatively regular tetragon-like shape with square top faces. At 3500–2700 cm −1 was the intensities of O–H stretching vibration bands while the 1400–600 cm −1 bands related to Ti–O vibration, sounded sharper and narrower, according to FTIR spectra for BST nanorods. The band gap of the BST nanorod films reduces from 3.1 to 2.95 eV as the reaction time of the prepared TiO 2 nanorods increased from 4 to 30 h. A strong photoluminescence centered at 366,362,364,368 nm are shown in BST nanorods. The absorbance curve revealed that the reflected wavelengths were in the range of 300–420 nm. Data of film reflectance can be used to calculate band gap energy ( E g ).