Green synthesis and characterisation of monometallic (Ni) and bimetallic (Ni-Ag) nanoparticles using Cicer Arietinum leaf extract and their applications for adsorption of toluidine blue

ABSTRACT

In this study, monometallic (Ni) and bimetallic (Ni-Ag) nanoparticles were synthesised by a bio reduction approach using Cicer Arietinum leaf extract which is known to contain high amount of phenolic and flavonoid compounds that can serve as nano-bio sources for synthesis metallic NPs. Biosynthesised nanoparticles were characterised using various techniques viz UV-Vis, FE-SEM, EDX, and XRD. The average crystallite diameter was found to be 30 nm and 24 nm for NiNPs and Ni-AgNPs, respectively, with almost spherical shapes, regular morphology and homogenously formed. The synthesised NPs were successfully applied for adsorption of toluidine blue dye (TBO) in aqueous solution using batch experiments with different process parameters namely initial dye concentration, contact time, pH, adsorbent dosage, and temperature. The adsorption isotherms and kinetics were investigated in detailed; the results followed Freundlich model (R² = 0.990, 0.976) and pseudo-second-order kinetic (R² = 0.998, 0.999) for both mono and bimetallic NPs, respectively. Finally, adsorption process showed that bimetallic Ag-NiNPs (q_e = 94 mg g⁻¹) could be considered more efficient for removal of TBO dye than NiNPs (q_e = 87 mg g⁻¹).

KEYWORDS:

• Cicer Arietinum leaf extract
• NiNPs
• Ni-AgNPs
• adsorption
• toluidine blue

Acknowledgments

The authors would like to thank Department of Chemistry/ University of Zakho for supporting this project.

Disclosure statement

No potential conflict of interest was reported by the author(s).