Synthesis and characterization of LaSmTiZrO7-SnSe composite for visible-light induced photocatalytic mineralization of Monoazo dyes

Abstract

Owing to the boom in textile industry in the recent past, there is a stringent requirement to deal with the environmental hazards associated with the azo dyes, a run-off from textile industry, i.e. toxicity to aquatic life and health hazards to humans. The use of nano-sized catalysts for the degradation of these dyes into minerals using sunlight as a primary source of energy is proved as most promising approach to handle the problem. The development of visible light sensitive catalysts is of great concern for the practical realization of dyes degradation. In the present work, we have synthesized LaSmTiZrO7 via microemulsion technique, while SnSe and their composite by using the hydrothermal approach. The XRD analysis confirmed the formation of LaSmTiZrO7, SnSe and their composite. The morphology, specific surface area, oxidation states of elements, surface chemical composition and optical properties of photocatalyst studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) nitrogen adsorption–desorption, X-ray photoelectron spectroscopy (XPS), energy dispersive spectra (EDS) and UV–vis spectroscopy, respectively. The synthesized catalytic materials have then been used for the photocatalytic degradation of mono azo foron blue dye under the visible-light irradiation. The alignment of energy levels shows that the electrons/holes recombination can be minimized with the formation of LaSmTiZrO7-SnSe composite. The photodegradation results confirm that the composite has better efficiency under visible light irradiation as compared to that of individual catalysts. The XRD analysis after photodegradation process confirms the structural stability of the composite.