"(BRI) Hyrbid Plasmonic-MOF Nanoparticle Superlattices

This proposal focuses on designing new hybrid nanoparticle (NP) constructs functionalized with programmable biological entities that can be assembled into new classes of hybrid superlattices. Our ultimate goal is to obtain specific architectures whose physical properties can be exploited for light-initiated and temperature-sensitive stoichiometric and catalytic chemistry. Specifically, we will focus on synthesizing novel building blocks from two general classes of materials: metal NPs1,2 and metal organic framework (MOF) NPs (nanoMOFs) (including infinite coordination polymers, ICPs, which are amorphous MOFs).3,4 With these nanoconstructs, we propose to use the design rules of DNA-programmable assembly to create crystalline lattices where the lattice symmetry and periodicity of the NPs can be controlled with sub-nm precision.5 By introducing MOFs into such NP superlattices for the first time, we will be able to produce novel materials with stoichiometric and catalytic chemistries that can be modulated by photo-excitation of nearby plasmonic particles (Figure 1). In principle, by adjusting the size, shape and composition of the metal NPs in the lattices, we can use different wavelengths of light to control the state of hybridization and chemistry of the nanoMOFs through local heating and orthogonal events. We will determine the collective properties of the hybrid NP superlattices using nonlinear and ultra-fast spectroscopies. Moreover, these tools will enable us to determine local order at the single nanoconstruct level based on electromagnetic field enhancements (as well as local nanoscale heating) and to potentially probe catalytic reactions at very low concentrations. In addition to our structure-determines-function investigations, we propose to execute an inverse approach to this problem using genetic algorithms, where function-determines-structure. In this way, we can identify a desired physical property of the hybrid superlattice (e.g. temperature increase) or its constituent materials (e.g. wavelength of plasmon resonance) and then work to build the hybrid NP superlattice in order to achieve this physical property.