Green synthesis of ZnFe2O4 nanoparticles using Chrysanthemum spp. flower extract for the adsorption and photocatalytic degradation of malachite green dye

BACKGROUNDNowadays, the large amount of organic textile dyes being regularly consumed also releases hazardous residues into water sources. Nanotechnology can solve part of this problem by using nanoparticles as adsorbents and catalysts for the removal of dyes from water. The present study explored the facile and green synthesis of ZnFe2O4 nanoparticles using Chrysanthemum spp. flower‐mediated extract (ZFOB) as a reducing and capping agent for the removal of cationic malachite green (MG). ZFOB nanoparticles were characterized by various techniques, such as X‐ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy.RESULTSThe average particle size and Brunauer‐Emmett‐Teller (BET) surface area of ZFOB were found to be 60–80 nm and 10.9 m2/g, respectively. The pore size distribution indicated a characteristic of meso‐macropores of the biosynthesized ZFOB nanoparticles. The MG adsorption of the green ZFOB nanoparticles was investigated under batch mode through the effect of various parameters, including contact time (0–60 min), initial concentration (5–100 mg/L), pH (4.0–10.0), and adsorbent dosage (0.25–1.0 g/L). The adsorption process followed the Elovich kinetic model, (Radj.2) = 0.9992, while the adsorption behavior can be described by Koble‐Corrigan, (Radj.2) = 0.9915. Meanwhile, the maximum adsorption capacity was 121.2 mg/g from the Langmuir model at a contact time of 30 min, dosage of 0.5 g/L, and pH 7. Green ZFOB nanoparticles showed a good photocatalytic activity (80.4%) under solar light irradiation and they were able to be recycled up to four times while retaining their high stability.CONCLUSIONZnFe2O4 nanoparticles biosynthesized using Chrysanthemum spp. flower extract can be a good adsorbent and photocatalyst for the removal of MG dye. © 2022 Society of Chemical Industry (SCI).