Photocatalytic dye degradation using sapota peel waste for environmental application

Abstract

The persistent and toxic nature of synthetic dyes poses a significant environmental threat, necessitating the development of sustainable and eco-friendly remediation strategies. This study explores the innovative synthesis and application of green-synthesized silver nanoparticles (AgNPs) derived from Manilkara zapota (sapota) peel waste for the photocatalytic degradation of harmful dyes. The AgNPs were synthesized using aqueous sapota peel extract and silver nitrate (1 mM) and were characterized by UV–Visible spectrophotometry, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), high-resolution scanning electron microscopy (HR-SEM), energy dispersive X-ray (EDX) spectroscopy, and dynamic light scattering (DLS) analysis. These techniques confirmed the formation of stable, quasi-spherical AgNPs with an average size of 75.46 nm and a zeta potential of − 9.35 mV. The study further investigated the photocatalytic efficiency of these AgNPs under sunlight irradiation, focusing on the degradation of malachite green (MG) and methylene blue (MB) dyes. UV–Visible spectrophotometry revealed a significant reduction in the main absorption peaks at 617 nm for MG and 664 nm for MB, indicating effective degradation. The results demonstrated near-complete degradation of MG (~ 100%) within 240 min and substantial degradation of MB (~ 80%) within 120 min. This research highlights the potential of utilizing sapota peel waste to develop green and efficient AgNPs for water pollution remediation, presenting a promising solution to the environmental challenges posed by synthetic dyes.