# A Green Sol–Gel Route to Fe3O4@TiO2–CuO Photocatalysts with Structural Stability, Visible–Light Activity, and Magnetic Recoverability

## TL;DR

This paper introduces a new photocatalyst made using plant extract and urea, which efficiently degrades pollutants under visible light and can be easily recovered using magnets.

## Contribution

The novel use of Magonia pubescens extract and urea-assisted pH modulation enables a stable, magnetically recoverable photocatalyst with visible-light activity.

## Key findings

- The Fe3O4@TiO2–CuO composite achieved 75% degradation of rhodamine B after 5 hours of visible light exposure.
- The catalyst retained over 45% activity after four reuse cycles due to magnetic recovery.
- Urea-assisted synthesis reduced iron leaching by 50%, enhancing structural and magnetic stability.

## Abstract

In this work, we present the synthesis of a multifunctional
Fe3O4@TiO2–CuO photocatalyst,
integrating Magonia pubescens plant
extract and urea-assisted
pH modulation. The as-prepared composite exhibits outstanding visible-light
photocatalytic performance, achieving 75% degradation of rhodamine
B (RhB, 15 ppm) after 5 h under 100 W LED irradiation and retaining
more than 45% activity across four reuse cycles enabled by simple
magnetic recovery. Notably, urea-assisted synthesis reduces iron leaching
by ∼50%, preserving magnetic integrity and enabling efficient
catalyst separation. Comprehensive structural, morphological, and
surface analyses (TEM, XRD, XPS, XRF, VSM, ICP, GC–MS) confirm
the formation of a robust, magnetically recoverable hybrid with a
narrowed band gap of 1.65 eV and enhanced stability. GC–MS
analysis revealed progressive mineralization of RhB into low-molecular-weight
intermediates.