Green Synthesis of Silver-Copper Core-Shell Nanoparticles Using Extract of Podocarpus gracilior and Their Catalytic Efficiencies

International Journal of Chemistry | Vol. 17, No. 7, July 2026 | pp. 49–56

DOI: 10.46882/2026/IJC/000213

Article Type: Original Research Paper

Title: Green Synthesis of Silver-Copper Core-Shell Nanoparticles Using Extract of Podocarpus gracilior and Their Catalytic Efficiencies

Names of Authors: S. I. Musa¹, K. A. Al-Jubouri²*

Authors’ Affiliations:
¹Department of Chemistry, University of Jos, Jos, Nigeria.
²Department of Chemistry, University of Baghdad, Baghdad, Iraq.

Abstract: The biological synthesis of bimetallic noble metal nanoparticles using medicinal plant extracts offers an eco-friendly and economically sustainable alternative to traditional chemical reduction protocols. This study details the green synthesis of stable copper-silver (Cu-Ag) core-shell nanoparticles utilizing the aqueous leaf extract of Podocarpus gracilior as both a reducing and stabilizing agent. The bioreduction process was monitored via UV-Vis spectrophotometry, which revealed the gradual decay and disappearance of the metal precursor bands over 60 minutes. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses showed highly spherical nanoparticles with an average particle diameter of 16 nm. X-ray diffraction (XRD) patterns confirmed the shell crystalline structure of the biosynthesized bimetallic system. Fourier-transform infrared (FT-IR) spectroscopy indicated that water-soluble biomolecules, primarily flavonoids and terpenoids within the leaf matrix, were responsible for capping and protecting the nanoparticles against structural agglomeration. The catalytic efficiency of the synthesized Cu-Ag nanoparticles was evaluated by tracking the reduction of rhodamine B dye by sodium borohydride (NaBH₄) in an aqueous system. In the absence of a catalyst, the reaction proceeded slowly, but the introduction of bimetallic nanoparticles accelerated the degradation process, achieving 97.4% decolorization within 10 minutes, outperforming monometallic controls.

Keywords: Bimetallic nanoparticles; Green synthesis; Podocarpus gracilior; Core-shell structure; Heterogeneous catalysis; Rhodamine B degradation

Manuscript Timeline: Received: October 12, 2024; Revised: November 24, 2024; Accepted: December 18, 2024; Published: July 08, 2026.

Citation: Musa, S. I., & Al-Jubouri, K. A. (2025). Green Synthesis of Silver-Copper Core-Shell Nanoparticles Using Extract of Podocarpus gracilior and Their Catalytic Efficiencies. International Journal of Chemistry, 17(7), 49–56.

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