Green synthesis of AlFeO3 nanoparticles using tragacanth gum as a photocatalyst in degradation of Congo red dye from aqueous solution

ABO3 type perovskites are of abiding interest to both experimentalists and theoreticians due to their practical applications in catalysis, sensing, magnetoresistance devices and spintronics. In addition to their engineering relevance, recent studies have revealed rich underlying physics. ABO3 type perovskite oxides with B-site doping have been extensively studied to optimize relevant physical properties such as ferroelectricity, superconductivity, and ferromagnetism in the product phases. It may be noted that typically, in this system, the A sites are occupied by divalent or trivalent metals and the B sites are occupied by tetravalent or trivalent ions. B cations are known to be substantial determinants of the physical properties of the ABO3 system. This is due to the localized and/or collective behavior of the d-electrons associated with the B ion. Iron-based semiconductors (AFeO3), such as BiFeO3, LaFeO3, YFeO3 etc., have also drawn attention in recent years; primarily owing to the possibility of developing narrow band gap semiconductors, and hence opening new possibilities for harnessing sun light (eg. through visible light photocatalysis) [1-3]. AFeO3 has also found a unique place in research of ferroic systems. In fact one of the recent developments in this family of perovskite oxides is the discovery of ferroelectricity and magnetic ordering in AlFeO3 material. An important report comes from the experimental work of Bouree et al. [4], wherein they reported the synthesis and detailed study of the crystal structure of AlFeO3. They also studied the magnetic structure of piezoelectric, ferrimagnetic and magnetoelectric properties of AlFeO3 from neutron powder diffraction. AlFeO3 nanoparticles have been produced via a simple green method from zinc nitrate, iron nitrate and tragacanth gel as biotemplate. Prepared AlFeO3 nanoparticles (NPs) were investigated by employing through X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission-scanning electron microscope (FE-SEM), and energy dispersive X-ray analysis (EDX), respectively. XRD, FTIR, EDX show that the highly pure AlFeO3 nanostructures. Moreover, the photocatalytic activity of synthesized AlFeO3 in the reduction of Congo red dye under visible light irradiation was studied by UV–Vis spectroscopy. The effects of initial dye concentration, photocatalyst dose, and visible light irradiation on dye degradation were assessed. The results exhibition that the catalyst could remove ca. 93% of the Congo red dye.