Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Green synthesis of morphologically controlled silver nanoparticles using ultrasonic energy and 505 nm light emitting diode irradiation

The development of safe, sustainable methods for silver nanoparticle (AgNP) synthesis remains a critical bottleneck in the advancement of nanotechnology. Traditional AgNP syntheses often relies on harsh reducing agents such as sodium borohydride and N,N-dimethylformamide which pose environmental and explosive safety hazards. Shaped AgNP synthesis in particular is often dangerous and difficult, and very few green syntheses exist. These difficulties and dangers also prevent nanoscience from being widely taught or studied in universities and schools lacking specialized setups. To these ends, our method employs a green approach for synthesizing morphologically controlled silver nanoparticles (AgNPs) using nothing but non-toxic plant-based sugars, ultrasonic energy, and light-emitting diode (LED) radiation to “pull” nanoparticles into non-spherical shapes. Here we show that cyan (505 nm) LED radiation can be used to create hexagonal and then triangular AgNPs which are highly stable over time. UV-visible spectroscopy is used to track the shape transformation progress as this cause shifts in the surface plasmon resonance wavelength which corresponds to spectacular color changes in the reaction solution. By emphasizing low-cost materials and minimizing hazardous reagents, this work contributes to the broader goals of green chemistry. Ultimately, this novel and green method produces shape-controlled AgNPs with potential applications in sensors, chemical probes, antimicrobial applications, all while offering an accessible route for bringing nanomaterial science into the classroom.