Synthesis of SmMnO3/Sm2O3 nanocomposites as efficient photocatalysts for organic dye degradation by sol gel pechini method

Abstract

In this research, we present SmMnO3/Sm2O3 nanocomposites as a novel ferromagnetic photocatalyst, synthesized through a straightforward sol-gel Pechini method utilizing citric acid and oxalic acid as fuels. Achieving the desired morphology involved varying the fuel type and calcination temperature. Comprehensive physicochemical characterizations were conducted using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), diffuse reflectance spectroscopy (DRS), and Brunauer-Emmett-Teller BET. With a band gap of 2.1 eV in the visible range, the SmMnO3/Sm2O3 nanocomposites exhibit promising optical properties. The photocatalytic prowess of these nanocomposites was systematically assessed against Malachite Green and Acid Red, with optimization of key parameters such as light source, pollutant concentration, and catalyst dosage. Notably, the peak photocatalytic activity was observed for Malachite Green, achieving an impressive 96% degradation under visible light within 120 min. The elucidation of the photocatalytic mechanism employed scavengers, revealing the pivotal role of OH• in the photodegradation process. Recycling experiments demonstrated consistent and acceptable results over five cycles, affirming the recyclability and durability of the SmMnO3/Sm2O3 nanocomposites. This study introduces a novel ferromagnetic photocatalyst with notable photocatalytic efficiency, emphasizing its potential applications in environmental remediation. The novelty of this work lies in the introduction of a new nanocomposite for photocatalysis in visible light, achieving high efficiency within a short time frame of 120 min.