Synthesis of Fe-ZSM-5 zeolite from high iron-containing palygorskite with peroxidase-like catalytic performance

Abstract

Zeolite products synthesized from mineral materials are receiving widespread attention, while there are few reports on the introduction of heteroatom metals from minerals into zeolites. Herein, the effects of different silicon sources, hydrothermal reaction time and the amount of template on the crystallisation of Fe-ZSM-5 were investigated. The morphology and structure of ZSM-5 were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), X-ray electron spectroscopy (XPS) and scanning electron microscopy (SEM). The catalysis of 3,3′,5,5′-tetramethylbenzidine (TMB) by Fe-ZSM-5 was then carried out to evaluate its enzyme-like catalytic performance as a type of nanozyme catalyst. The results showed that Fe-ZSM-5 exhibited peroxidase-like activity, oxidizing TMB into a colored substance in the presence of hydrogen peroxide (H₂O₂). Kinetic analysis implied that, compared with natural horseradish peroxidase (HRP), Fe-ZSM-5 peroxidase mimics exhibit inferior affinity and enzymatic catalytic velocity towards the TMB substrate. However, it exhibited excellent stability under extreme pH, temperature, and ionic strength conditions. This work provides a possible reference for the construction of functional nanozymes using natural mineral resources.