Biomimetic Synthesis of Heterogeneous Catalysts

The scope of this proposal is the design and biomimetic synthesis of heterogeneous catalysts using a carbon nanotube (CNT) scaffold. Fabrication of complex multicomponent supported nanomaterials on CNTs is difficult. Standard production is limited by two factors: the extreme oxidative conditions required for CNT pretreatment, resulting in tube damage, and the composition and arrangement of the surface materials. Conversely, biomimetic approaches to materials synthesis have elucidated numerous peptides that are responsible for production of various materials, ranging from metallic and semiconducting nanoparticles to metal oxide species, at ambient conditions. This proposal will focus on the interface of these two areas and use peptide modified CNTs for the production of heterogeneous multimetallic catalysts. Three selected peptidyl sequences, with affinities for the production of catalytically active Pd and Au nanoparticles and porous Sioz, will be bound to the nanotube support under ambient conditions. Once attached, production of Pd and Au nanoparticles along the nanotube will be possible. Subsequently, a porous Sioz matrix can be fabricated along the composite surface, resulting in a metal-in-oxide heterogeneous catalyst. Production of various surface metallic compositions will be carried out by varying the amount of each peptide attached to the CNT, resulting in selectable metal cluster distances. Once the synthesis of the materials is complete, the effects of composition and specific particle location for catalytic hydrogenation will be examined. The ultimate goal of this proposal is the fine-tuning of catalytic activity for development of the next generation of olefin hydrogenation catalysts for use in petroleum refining processes.