Fabrication of high-performance multifunctional Fe-doped La2ZnTiO6 double perovskite/activated carbon nanocomposite for efficient photocatalytic degradation of dyes, nitrate and carbon dioxide pollutants

Abstract

Nowadays, among the different environmental pollutants; nitrate (NO3−), carbon dioxide (CO2), and organic dyes have created serious concern worldwide. Therefore, the synthesis of a high-performance photocatalyst for the simultaneous and effective removal of these pollutants is taken into consideration. In this research, Fe-doped La2ZnTiO6/activated carbon multifunctional photocatalyst was used to degradation of dyes (Rhodamine-b (RhB) cation dye and acid red 14 (AR14) anion dye), NO3−, and CO2 pollutants under visible light irradiation. The structural properties of synthesized photocatalyst were characterized by X-ray diffraction, scanning electron microscopy, and Energy-dispersive X-ray/mapping (EDX-Map) analysis. In addition, the photocatalytic activity of Fe-doped La2ZnTiO6/activated carbon nanocomposite was investigated by UV–visible analysis, Diffuse reflectance spectroscopy, and photoluminescence technique. The UV–visible spectrums were indicated the degradation percentage of 88.24% for RhB cation dye and degradation efficiency of 86.67% for AR14 anion dye in experiment conditions of pH;7, temperature (T); 65 °C, stirring speed (S); 200 rpm, time retention (t); 5h, photocatalyst dosage [catalyst]; 1 g/L, dye concentration [dye]o; 10 mg/L and distance between the surface of the solution and visible light source; 10 cm under visible light irradiation. In addition, the maximum removal value of NO3− pollutant from aqueous solution was determined about 86.67% in experiment conditions of pH; 3, temperature; 25 °C, agitation rate; 200 rpm, time reaction; 3h, photocatalyst dosage; 1 g/l, NO3−concentration; 100 mg/L and distance between the surface of the solution and light source; 10 cm under visible light irradiation, respectively. Finally, degradation and conversion maximum of CO2 pollutant was obtained at about 80% in test conditions of pH; 3, temperature; 25 °C, mixing rate; 200 rpm, time reaction; 3h, photocatalyst dosage; 1 g/L, CO2 concentration; 100 mg/L and distance between the surface of the solution and light source; 10 cm under visible light irradiation.