Alejandro Díaz Ortiz –
Air-stable nanoparticle arrays for ultrahigh density recording and medical applications

The most important factor in the synthesis of functional multi-component nanoparticles (NPs) is the precise control over the size, composition, structure, and pattern formation. The vast field of NP synthesis can be classified in two main groups: (a) dense assemblies of interacting NPs and (b) dilute non-interacting NPs. The former profits from the fact that the constitutive NPs act as artificial atoms, thus creating materials that rely mainly on the collective response of the system. Such configurations serve well in photonic, photovoltaic, and energy storage systems.

The dilute NP scheme, on the other hand, depends on the properties and performance of the individual NPs, as in biomedical (e.g., imaging and tumor therapy) or catalytic systems, where size and structure of the individual components dictate efficiency and functionality. Two-dimensional arrays of NPs on substrates provide an interesting and exciting regime where the individual and collective properties of the constitutive NPs can be exploited simultaneously. Such architectures are the cornerstone for NP-based magnetic data-storage devices, biosensors, as well as functional interfaces to tailor cell-matrix interaction.

In this research project we aim to control the architecture of NP assemblies, that is, the size and composition of the particles and their distribution on a substrate. Recently, we have advanced the diblock copolymer nanolithography approach to the self-assembly of multicomponent (binary and ternary) CS NPs on surfaces that renders well-defined 2D NP arrays of tunable architecture. Using this technique, we have succeeded in producing corrosion resistance Fe-Co@Au NPs (read our recent paper).


Collaborators:
Beri M. Mbenkum, Modern Magnetic Materials Department, MPI-MF, Stuttgart
Lin Gu, Advanced Institute for Materials Research, Japan
Peter van Aken, Stuttgart Center for Electron Microscopy, MPI-MF, Stuttgart