Ultrastable Silver Nanoparticles


Project ID:  D2014-05



Silver nanoparticles have shown huge technological promise in wide variety of applications due to their superior optical properties, bioactivity, and diversity of chemical and photochemical properties. However, the main challenge with silver nanoparticle is its chemical instability to oxidation, i.e. tarnishing, which has limited the development of technologically important nanomaterials. Despite two decades of synthetic efforts, chemically inert and long-term stable Ag nanoparticles remain unrealized.


Invention Description

Researchers at The University of Toledo have developed an entirely new approach to preparing ultra-stable silver nanoparticles. With judicious choice of solvent conditions and stabilizing agents, the researchers have transformed fragile and unstable Ag complexes into chemically inert materials with unprecedented stability. It is an easy, highly efficient, and commercially affordable synthetic protocol, producing ultra-stable pure molecular materials and in exceptionally large yields. The stability, purity, and yield of these Ag nanoclusters are substantially better than any other metal nanoparticle, including gold, indicating a different mechanism for stability. Its unique chemical stability and structural, electronic and optical properties are accounted for by a chemically complete structural model and an exceptionally stable Ag32 core, tested by high-level electronic structure theory.



•       Can be used as a metallization precursor, antibiotics, microscopy stains/markers, inks and dyes

•       Potential use in medical industry, food storage, textile coatings, metallization, silver inks, dye-sensitized solar cells and a number of environmental applications



•       No principle upper limit to the scale of the synthesis due to the exceptional thermodynamic stability of the clusters

•       Unprecedented purity and yield, far superior to previous methods

•       Long term stability in solid or solution forms

•       Fast, easy, and inexpensive to synthesize 

•       Single-sized molecular product without the need for size sorting

•       Consistent results; single-sized molecular product with no size separations


IP Status:        Patent 9,765,094



1.    Nature 2013. Desireddy et al. Ultrastable silver nanoparticles.

2.    Nature materials 2014. Yoon et al. Hydrogen-bonded structure and mechanical chiral response of a silver nanoparticle superlattice.


Patent Information:
For Information, Contact:
Katherine Pollard
Licensing Associate
The University of Toledo
Terry Bigioni
Anil Desireddy
Brian Conn