The importance of stirring for achieving uniformity and effective gas exchange has been well-established over the years. Regulating the stirring speed during the synthesis of nanoclusters is essential for producing nanostructures with specific sizes, shapes, optical characteristics, and stability. This concept was emphasized in a recent study led by Director Bartosz A. GRZYBOWSKI from the Center for Algorithmic and Robotized Synthesis at the Institute for Basic Science.
In their investigation, the researchers focused on synthesizing fluorescent silver nanoclusters within a traditional sodium borohydride/glutathione framework. They discovered that the timely and appropriate delivery of oxygen to the mixture significantly influenced the synthesis outcomes.
The characteristics of the resulting nanostructures could be finely adjusted—from being unstable and non-fluorescent to highly fluorescent—simply through modifications in the stirring conditions. A minor adjustment in the size of the stirring bar, from 25 by 12 mm to 20 by 10 mm, while maintaining the same stirring speed, consistently produced a non-fluorescent result.
Furthermore, oxygen was identified as a crucial element that affects the structure and functional attributes of silver nanoclusters. By providing substantial amounts of oxygen under carefully managed stirring conditions, researchers were able to produce fluorescent silver nanoclusters with exceptional stability, preserving their fluorescence for over two years.
“As a chemist, I found it fascinating that oxygen didn’t just ‘ruin’ or oxidize the silver; rather, its presence in the silver lattice of the forming nanoclusters contributed to the longevity of the fluorescence,” remarked Director Grzybowski, the team leader.
The remarkable stability of these silver nanoclusters could lead to expanded applications in fields such as catalysis, biosensing, and bioimaging.
This research deepens our understanding of how the structure of nanostructures relates to their properties, facilitating the flexible design of nanomaterials with customized attributes and broadening their potential applications.
