Photocatalytic Oxidation of Isopropanol in Aqueous Solution Using Perovskite‐Structured La₂Ti₂O₇

Abstract

This study is focused on the application of a highly-doped layered perovskite, La 2-Ti 2 O 7 , as the photocatalyst for the photocatalytic decomposition of isopropanol (IPA). The La 2 Ti 2 O 7 powder prepared by solid state reaction was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectrophotometry (UV-DRS), X-ray photoelectron spectroscopy (XPS), and zeta potential. The temporal behavior of the photocatalytic decomposition of IPA in aqueous solution by the UV/La 2 Ti 2 O 7 , with a photoreactor operated in a recirculation mode, was studied under various conditions including solution pH, light intensity, and La 2 Ti 2 O 7 loading. The decomposition of IPA in aqueous solution by La 2 Ti 2 O 7 photocatalytic processes was found to be technically feasible. A kinetic equation was developed for modeling the photocatalytic decomposition of IPA by the UV/La 2 Ti 2 O 7 photocatalytic processes.

Synthesis and characterization of La2Ti2O7 employed for photocatalytic degradation of reactive red 22 dyestuff in aqueous solution

“…The UV-vis DRS patterns for La 2 Ti 2 O 7 prepared in this study by PC method was measured in the wavelength range of 200-800 nm, and are compared with the results for La 2 Ti 2 O 7 prepared by SSR method from our previous study [6], as illustrated in Fig. 5.…”

“…However, the rapid recombination of photogenerated electron-hole pairs critically limits the effectiveness of photocatalytic processes. Recently, several new perovskite structured photocatalysts with highly donor-doped layered structures have been found to be competent on photocatalytic applications, including water-splitting [1][2][3], Cr(VI) reduction [4], NO oxidation [5] and decomposition of organic compounds [6,7]. Perovskites contains a cubic structure with three different ions, as form of ABO 3 [8].…”

“…Perovskites contains a cubic structure with three different ions, as form of ABO 3 [8]. A series of perovskite structured photocatalysts, such as LaNiO 3 [7], Bi 4 Ti 3 O 12 [9,10], Bi 2 Zn 2/3−x Cu x Ta 4/3 O 7 [11], BiVO 4 [12] and La 2 Ti 2 O 7 [6], have been investigated over their photocatalytic properties and applications. The separation of electrons and holes in the perovskites is easier than that in other semiconductor materials because of their narrower depletion layers.…”

A survey of photocatalytic materials for environmental remediation

“…Both catalysts showed high photocatalytic activity for the photodegradation of MO under UV irradiation and, in particular, the photoactivity of Bi 2 Ti 2 O 7 was much higher than that of P25 [371]. Layered perovskite La 2 Ti 2 O 7 prepared by a solid-state reaction was efficiently employed for the decomposition of an aqueous solution of 2-propanol [372].…”

Optical properties of Ln2Ti2O7 (with Ln = La to Lu) thin films grown on (110)-SrTiO3 substrates by pulsed laser deposition

“…All of these Ln 2 Ti 2 O 7 oxides can be employed in photo-electrochemical systems as a photo-catalyst (e.g. for the water-splitting [12], [13], for the photo-degradation of organic pollutants [14], [15], [16] and/or for the photo-reduction of inorganic ions in water, like for example the reduction of Cr(VI) to Cr(III) [17]). A photocatalyst, such as La 2 Ti 2 O 7 , requires the use of an excitation energy in UV domain.…”