Ferrocenylselenoether and its cuprous cluster modified TiO2 as visible-light photocatalyst for the synergistic transformation of N-cyclic organics and Cr(vi)

Abstract

In this study, fcSe@TiO₂ and [Cu₂I₂(fcSe)₂]_n@TiO₂ nanosystems based on ferrocenylselenoether and its cuprous cluster were developed and characterized by X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), energy dispersive X-ray spectroscopy (EDX), and electron paramagnetic resonance (EPR). Under optimized conditions, 0.2 g L⁻¹ catalyst, 20 mM H₂O₂, and initial pH 7, good synergistic visible light photocatalytic tetracycline degradation and Cr(VI) reduction were achieved, with 92.1% of tetracycline and 64.5% of Cr(VI) removal efficiency within 30 minutes. Mechanistic studies revealed that the reactive species ˙OH, ˙O₂⁻, and h⁺ were produced in both systems through the mutual promotion of Fenton reactions and photogenerated charge separation. The [Cu₂I₂(fcSe)₂]_n@TiO₂ system additionally produced ¹O₂ from Cu⁺ and ˙O₂⁻. The advantages of the developed nanosystems include an acidic surface microenvironment provided by Se⋯H⁺, resourceful product formation, tolerance of complex environments, and excellent adaptability in refractory N-cyclic organics.