Synthesis, characterization and photocatalytic activity of engelhard titanosilicates (Ets-4)

Abstract

Engelhard Titanosilicate-4 (ETS-4) is a microporous zeo-type. material which contains framework of semiconductive monoatoiruc -O-Ti^-O- chains that useful for photocatalysis. In this study, ETS- 4 materials were synthesized by the hydrothermal method using two different initial molar compositions. The hydrothermal synthesis reactions were performed at 200"C for 6, 12, and 24 h in a Teflonlined autoclave. The prepared ETS-4 materials were characterized using several techniques such as X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Bruneuer. Emmet Teller (BET) surface analysis. The parameters of Si:Ti ratio as wet! as synthesis time and reactions on photocatalytic activity of ETS-4 were investigated using photodegradation reaction of Rhodamine B dye under Ultraviolet (UV) light irradiation The change in concentration with varied irradiation time was monitored by determining its absorbance at 554 nm using UV-Visible spectrophotometer. The absorption spectra results show ETS-4(B) materials which were produced at lower Si:Ti ratio exhibited better photocatalytic activity than ETS-4(A) which is due to higher surface area and higher content of Ti-OH groups.