Green synthesis of ZIF-67 composite embedded with magnetic nanoparticles and ZnO decoration for efficient catalytic reduction of rhodamine B and methylene blue

Abstract

This work focused on the green synthesis of the composite material Fe₃O₄/ZIF-67@ZnO utilizing magnetic and ZnO nanoparticles aided by lime extract. The composite was characterized through FTIR, XRD, FESEM, EDX, and TGA techniques. FTIR confirmed the presence of characteristic functional groups. XRD revealed the crystalline nature of the composite. FESEM images revealed spherical aggregation and a rough surface morphology. EDX analysis confirmed the uniform distribution of different elements, indicating successful incorporation. The TGA results showed that the thermal stability of the composite was enhanced owing to the nanoparticles. The composite was applied as a catalyst for reducing the organic dyes Rhodamine B (RhB) and Methylene Blue (MB). The effects of varying dosages and dye concentrations were systematically studied. It exhibited significant catalytic efficiency, reducing 88.2 ​% of RhB (11 ​min) and 87.3 ​% of MB (9 ​min). The reduction followed pseudo-first-order kinetics and synthesized composite could be reused for at least five cycles. These findings demonstrate the promising catalytic properties of the Fe₃O₄/ZIF-67@ZnO composite, especially for environmental remediation applications.