Visible-light-active and biocompatible ScxLu1-xFeO3 (x = 0, 0.5, 1.0) photocatalysts with magnetic functionality

https://doi.org/10.1016/j.cej.2025.168055

Development of multifunctional nanomaterials for visible-light-driven environmental remediation remains a major challenge in green chemical engineering. In this study, we report on solution combustion synthesis of biocompatible Sc_xLu_1-xFeO₃ (x = 0, 0.5, 1) nanocrystals with unique photocatalytic and magnetic properties. Structural characterization confirmed phase-pure formation of orthorhombic (o-LuFeO₃), hexagonal (h-Sc_0.5Lu_0.5FeO₃), and cubic (c-ScFeO₃) perovskite-type phases with crystallite sizes of 89.3, 36.7, and 54.3 nm, respectively. Morphologically, the materials exhibited a porous foam-like architecture with BET surface areas of 10.06–14.36 m²/g and dominant mesopores (3.9–11.2 nm). Diffuse reflectance spectroscopy revealed a strong visible-light absorption and narrow band gaps ranging from 1.97 to 2.30 eV. Under visible-light irradiation (λ = 410 nm), h-Sc_0.5Lu_0.5FeO₃ showed superior photocatalytic degradation of methylene blue, achieving 100 % removal within 30 min with a rate constant of 0.1448 min⁻¹, outperforming both o-LuFeO₃ (45 %, 0.0206 min⁻¹) and c-ScFeO₃ (60 %, 0.0321 min⁻¹). Magnetic studies revealed strong coercivity in o-LuFeO₃ (2.5 T), spin-glass-like features in h-Sc_0.5Lu_0.5FeO₃ (T_N = 151 K), and weak antiferromagnetism in c-ScFeO₃. Biocompatibility testing using THP-1 and K562 cell lines showed more than 80 % of cell survival at concentrations up to 0.25 mg/mL, with no significant morphological damage among THP-1 and K562 cells. Owing to their combined photocatalytic efficiency, magnetic separability, and biological safety, these materials are promising for integration into hybrid wastewater treatment systems as biocompatible visible-light-responsive photocatalysts.