Influence of tetrabutylammonium hydroxide on the microstructural, optical and photocatalytic properties of sol-gel derived Gd2Ti2O7 for RBR X-3B degradation

Tetrabutylammoniumhydroxide (TBAOH) was included in the solegel precursor to prepare the porous gadolinium titanates. The influences of the TBAOH template on the characteristics of the gadolinium titanates were investigated. The TBAOH played a key role for the porous structure in the samples. The sample obtained without TBAOH was composed of Gd2Ti2O7 crystals, while the crystallite size slightly decreased from 39.0 to 27.5 nm with rising TBAOH amount. The maximum BET surface area was 8.09 m(2)/g for the sample obtained using 1.2 mL of TBAOH, and the sample also had the largest external surface area of 7.19 m(2)/g. The bandgap energy was 3.36 eV for the material obtained without TBAOH, and the bandgap energy of the Gd2Ti2O7(m) was nearly unchanged after using different amount of TBAOH. The largest number of hydroxyl radicals were generated on the Gd2Ti2O7(1.2) sample, which had the strongest photocatalytic activity. After 150 min of reaction, the RBR X-3B degradation efficiencies were 29.3%, 93.4% and 41.4% on the Gd2Ti2O7(0), Gd2Ti2O7(1.2) and Gd2Ti2O7(1.8), respectively. The light absorption intensities of the organic groups in the dye were significantly reduced with extended reaction time. (C) 2021 The Authors. Published by Elsevier B.V.

Automated summary

In this study, porous gadolinium titanates were prepared using TBAOH as a template, which played a key role in the characteristics of the samples. The addition of TBAOH reduced the crystallite size, increased the specific surface area, and enhanced the photocatalytic activity of the samples.