Fruit peels as redox bio factories: Tailoring bimetallic nanoparticles via sustainable green chemistry

Abstract

Bimetallic nanoparticles (BimNPs) have emerged as multifunctional nanomaterials with superior properties compared to their monometallic counterparts, owing to synergistic interactions between metal pairs. This review comprehensively explores the green synthesis of BimNPs using phytochemical-rich fruit peels as sustainable, low-cost reducing and stabilizing agents. We detail mechanisms of nanoparticle formation driven by fruit-peel polyphenols and flavonoids. Commonly used fruit peels including banana, citrus, pomegranate, and papaya are analysed with respect to phytochemical composition, extraction techniques, and resultant BimNP characteristics. We discuss biomedical, environmental remediation, and sensing applications. Challenges related to reproducibility, scalability, toxicity, and regulatory gaps are highlighted, alongside future strategies involving artificial intelligence, advanced characterization, and the valorisation of underexplored peel sources. The review underscores the promising role of fruit-peel-based green nanotechnology in sustainable nanomaterial innovation.