Assembly of molecular metal oxides from the nano to the macroscale via chemical gardens

Assembly of Molecular Metal Oxides from the Nano to the Macroscale via Chemical Gardens
Lee Cronin, WestCHEM, School of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK
The organization of matter across length scales, starting from well defined building blocks, is a key
challenge in the design of advanced functional materials and devices. Patterned, or highly structured,
assemblies can be formed spontaneously in systems which are exposed to fluxes of matter and energy.
These assemblies can sustain themselves far from equilibrium whilst the fluxes are maintained, leading
to the emergence of temporal and spatial structures. In our work we opted to investigate such
assemblies using polyoxometalate clusters. Such clusters are interesting since their assembly can bridge
multiple length scales[1] from the assembly of sub-nanoscale to protein sized molecules and even
colloidal aggregates of clusters many hundreds of nm in size and have many interesting properties.[2]
Here, we present a range of approaches, using common inorganic oxide building blocks, to direct the
self-assembly of these dissolved inorganic molecular building blocks into robust, hollow tubular
networks, materials and inorganic chemical cells (iCHELLs).[3-5] The resulting architectures can be selected
to be inert or chemically active (e.g. catalytic). The result is a configurable system for directed assembly
of complex materials from nanomolecular oxide building blocks, with many possible applications from
new materials to micro-devices, and we also present the design of a minimal all-inorganic photosystem
based upon the above approaches.