Synthesis of TiO2/SiO2-B2O3 Ternary Nanocomposites: Influence of Interfacial Properties on their Photocatalytic Activities with High Resolution Mass Spectrometry Monitoring

Abstract

An investigation on unusual interface properties of unprecedented ternary composites, formed by the inclusion of assorted proportions of B 2 O 3 into TiO 2 /SiO 2 structure, is conducted herein. The influences of B 2 O 3 content and calcination temperature were evaluated. The precursor TiO 2 /SiO 2 material was synthesized via a simple sol-gel procedure that was followed by B 2 O 3 inclusion via maceration and calcination. The materials were fully characterized and their photocatalytic performance to degrade the Indigo Carmine dye investigated. The material prepared with a B/Ti molar ratio of 1 and at calcination temperature of 350 °C (B 1-350 ) showed the best performance, with a superior photocatalytic activity than that of commercial TiO 2 . The presence of B 2 O 3 -TiO 2 -SiO 2 interfaces in the structure of such material was of critical importance in producing a material with these attractive features. Finally, high resolution mass spectrometry monitoring allowed for the characterization of the main degradation products formed under these conditions.

Characterization and evaluation of the photocatalytic activity of oxides based on TiO2 synthesized by hydrolysis controlled by the use of water/acetone mixtures

“…5, and by applying the direct method, it was possible to estimate the band gap energies (Eg) of the photocatalysts (Liu & Li, 2012). The estimated Eg were as follows: 3.23 eV for W1, 3.24 eV for W1-25, 3.22 eV for W1-50, and 3.23 eV for W1-75, indicating that the estimated band gap energies have not undergone major changes, which agree with the data reported in the literature for pure TiO 2 (Martin-Somer et al, 2020;Neto et al, 2017;Resende et al, 2017). Most likely, this stems from the synthesis conditions adopted in this work, where none dopant material was added.…”

Supplemental Information 13: N2 adsorption-desorption isotherms obtained for the studied photocatalysts.

“…5, and by applying the direct method, it was possible to estimate the band gap energies (Eg) of the photocatalysts (Liu & Li, 2012). The estimated Eg were as follows: 3.23 eV for W1, 3.24 eV for W1-25, 3.22 eV for W1-50, and 3.23 eV for W1-75, indicating that the estimated band gap energies have not undergone major changes, which agree with the data reported in the literature for pure TiO 2 (Martin-Somer et al, 2020;Neto et al, 2017;Resende et al, 2017). Most likely, this stems from the synthesis conditions adopted in this work, where none dopant material was added.…”