Novel Method to Produce Uniformly Sized Nanoparticle Superclusters

According to Sharon Glotzer and Nicholas Kotov, chemical engineering professors at the University of Michigan, uniformly sized nanoparticle superclusters can be produced by assembling nanoparticles using a fine balance of atomic forces.

During the study, the researchers found when various sizes of nanoscale building blocks are used for the production of nanoparticle superclusters, the van der Waals attraction and electrostatic repulsion force counter balance one another, which in turn restricts cluster growth. This equilibrium allows the production of uniformly sized clusters.

The researchers used red, powdery cadmium selenide for the formation of the inorganic superclusters technically known as ‘supraparticles’. Kotov stated that the powdery material cannot be considered as artificial viruses but shared most of the properties of viruses, including core-shell pattern, shape, size as well as the capabilities to assemble and dissemble. The fact that these properties are present in inorganic materials is truly amazing and there is a possibility to couple these functionalities with the performance properties of inorganic materials, including electrical conductivity, light adsorption and environmental resilience.

The National Center of Nanoscience and Technology’s collaborating professor, Zhiyong Tang commented that supraparticles can be utilized as the building blocks to create three-dimensional ordered assemblies. This secondary self-assembly characteristic offers a viable method to produce large-scale nanostructures that are required for practical applications, he added.

At present, Kotov is involved in the formation of these supraparticles to manufacture synthetic fuels using carbon dioxide. The work also finds applications in solar cell development and drug delivery and it could drastically decrease the production costs of huge volumes of supraparticles.