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, ambient light, and 448 nm light emitting diode irradiation

Silver nanoparticles (AgNPs), which have unique optical, electrical, and antimicrobial properties, have a wide range of applications in a variety of fields including catalysis, sensing, and medicine. Traditional synthesis methods employ harsh chemicals that negatively impact the environment, and dangerous setups that can potentially harm the experimenter; therefore, the study of nanoscience is often out of reach for smaller institutions and classrooms. To address this need, we have developed an alternative, facile synthetic method that uses safe reagents and green energy sources to produce morphologically controlled AgNPs. Using nothing but sugars as reducing and capping agents, solutions are seeded using ultrasonic energy and then “pulled” into non-spherical shapes using nothing but LED and ambient light irradiation. Here we show that royal blue (448 nm) LED radiation can be used to create decahedral AgNPs, and when combined with ambient light exposure, a red-to-blue wavelength-tunable light-scattering AgNP solution is produced. The shape transformation reaction itself is also accompanied by vivid color changes and can be easily tracked using UV-visible spectroscopy. Not only does this novel synthetic method produce AgNPs with uniquely powerful optical qualities, it is also itself a visually stunning and safe way to bring nanoscience into any classroom or university. By strengthening nanoscience education and research at all levels, we hope to broaden access to this rapidly advancing field of study and enable the next generation of students to contribute to the future of nanotechnology.