Efficient removal of crystal violet from wastewater using a Zn–Fe layered double hydroxide: photocatalysis and antibacterial insights

 

Abstract

Zinc-based layered double hydroxide (Zn–Fe LDH) and its calcined mixed metal oxide (Zn–Fe MMO) were synthesized using a simple co-precipitation method. The materials were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and UV–visible diffuse reflectance spectroscopy (UV–vis DRS) to confirm their structural, morphological and optical properties. Both photocatalysts showed high efficiency in the visible-light degradation of crystal violet (CV) dye, achieving removal rates of ~ 95% for Zn–Fe LDH and 89% for Zn–Fe MMO under optimal conditions (10 mg catalyst, 10 mg L⁻¹ dye, neutral pH, room temperature). The photocatalytic mechanism, catalyst dosage effect, and kinetic behavior were systematically investigated. Additionally, both materials demonstrated effective antibacterial activity against Gram-positive and Gram-negative strains. These results highlight the potential of Zn–Fe LDH and Zn–Fe MMO for applications in environmental remediation and antibacterial treatments.

 

Link: https://link.springer.com/article/10.1007/s11144-025-02982-1