XPS\xa0and structural studies of Fe3O4-PTMS-NAS@Cu as a novel magnetic natural asphalt base network and recoverable nanocatalyst for the synthesis of biaryl compounds

Homa Kohzadi,Mohammad Soleiman-Beigi

doi:10.1038/s41598-021-04111-z

Abstract

In this research, natural asphalt as a mineral carbonuous material was converted to sodium natural asphalt sulfonate (Na-NAS) and, then, was linked to Fe3O4 MNPs in order to synthesize the magnetic nanocatalyst. Afterwards, Cupper (I) and Cu (II) was grafted on Fe3O4-PTMS-NAS. Moreover, it is worth mentioning that the synthesized the novel magnetic nanocatalyst (Fe3O4-PTMS-NAS@Cu) was successfully used in Suzuki and Stille coupling reactions. The Fe3O4-PTMS-NAS@Cu MNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), inductively coupled plasma (ICP), BET and X-ray photoelectron spectroscopy (XPS) analysis. Besides, sulfonation of natural asphalt, magnetization of catalyst, grafting of Cu (I) and Cu (II) to NAS and catalyst formation were investigated and proved carefully. This nanocatalyst can be comfortably separated from the reaction medium through an external magnetic field and can also be recovered and reused, while maintaining its catalytic activity.

Highlights

In this research, natural asphalt as a mineral carbonuous material was converted to sodium natural asphalt sulfonate (Na-NAS) and, was linked to Fe3O4 MNPs in order to synthesize the magnetic nanocatalyst
We have studied the activity of F e3O4-PTMS-NAS@Cu MNPs in the synthesis of compounds (2a) and (3a) after recovery
X-ray diffraction (XRD) was investigated using a Holland Philips X, the thermogravimetric analysis (TGA) curve was recorded using a PL-STA 1500 device manufactured by Thermal Sciences, superparamagnetic properties of the catalyst were measured using vibrating sample magnetometry (VSM) (MDKFD) and the analysis of the surface chemical composition of F e3O4-PTMS-NAS@Cu MNPs was conducted using the X-ray photoelectron spectroscopy (XPS) (Thermo Scientific, ESCALAB 250Xi Mg X-ray resource) see Supplementary Information

Summary

Introduction

Natural asphalt as a mineral carbonuous material was converted to sodium natural asphalt sulfonate (Na-NAS) and, was linked to Fe3O4 MNPs in order to synthesize the magnetic nanocatalyst. The EDX spectrum of the F e3O4-PTMS-NAS@Cu MNPs is demonstrated, which confirms the presence of Fe, O, S and Cu elements in the structure of the catalyst and proved that the magnetic nanoparticle has been successfully synthesized.

Results

Conclusion