Versatile Nanoparticle Synthesis Platform Using Spent Coffee Grounds

The development of sustainable methods for nanoparticle (NP) synthesis is vital as demand grows across physics, engineering, and materials science. Conventional fabrication often relies on hazardous reagents and energy intensive processes, motivating the search for cleaner alternatives. Previously, we showed that extracts from spent coffee grounds (SCGs) can serve as renewable reducing and stabilizing agents for silver and gold NP synthesis, confirmed by UV–Vis, fluorescence spectroscopy, and SEM.

Here, we extend this approach to oxide and carbon-based NPs, using SCG extracts as precursors, reducers, or stabilizers. Spectroscopic analyses reveal distinct optical signatures confirming the formation of these nanostructures, highlighting the versatility of SCG-derived biomolecules as universal reagents. FTIR further identifies functional groups responsible for NP stabilization.

These results establish a broadly applicable, waste-derived platform for producing diverse nanomaterials in an environmentally responsible manner. The scalability and adaptability of this method suggest potential applications in sensing, catalysis, biomedical, and energy technologies, advancing green chemistry in nanoscience.