A dual-functional Zn(II) coordination polymer for detection of Cr(VI) and photocatalytic degradation of rhodamine B in aqueous solution

Efficient photocatalytic degradation of Rhodamine B dye using solar light-driven La-Mn co-doped Fe2O3 nanoparticles

This work aims to develop a highly efficient solar light-induced photocatalyst based on La-Mn co-doped Fe₂O₃ nanoparticles. Pure Fe₂O₃ and La-Mn co-doped Fe₂O₃ nanoparticles were fabricated by a simple co-precipitation method. The photocatalysts were analyzed for their morphological, structural, and magnetic characteristics. Scanning electron microscopy analysis demonstrated the formation of semi-spherical nanoparticles along with small aggregations. The size of nanoparticles was measured using a transmission electron microscope and found in the range of 42-49 nm. The crystalline nature and geometry of synthesized nanoparticles were investigated using X-ray diffraction analysis. Due to the incorporation of La-Mn, the saturation magnetization and remanent magnetization of the nanoparticles decreased from 6.17 to 2.89 emu/g and 1.15 to 0.52 emu/g, respectively, while the coercivity was reduced from 756.72 to 756.67 Oe. The surface area of nanoparticles was increased from 77.93 to 87.45 m²/g as a result of La-Mn co-doping. The photocatalytic performance of the Fe₂O₃, La_0.1Mn_0.3Fe_1.6O₃, and La_0.2Mn_0.2Fe_1.6O₃ catalysts was assessed by their capability to degrade Rhodamine B (RhB) under solar light illumination. La_0.2Mn_0.2Fe_1.6O₃ displayed exceptional degradation performance, degrading RhB to 91.78% in 240 min, in comparison to La_0.1Mn_0.3Fe_1.6O₃ (71.09%) and pristine Fe₂O₃ (58.21%) under specified reaction conditions ((RhB) = 50 ppm; (catalyst) = 40 mg/L; pH = 7; T = 25 °C)). RhB degradation was affected by changing pH, catalytic dosage, dye concentration, and temperature. The degradation of RhB was found to be pseudo-1st order kinetics. The exceptional photocatalytic performance of La_0.2Mn_0.2Fe_1.6O₃ catalysts showed that the synthesized nanoparticles could be effectively utilized to remove organic pollutants from industrial wastewater.