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Photoelectrosynthetic assemblies provide an approach to capture, convert, and store solar energy as a fuel. However, the ability to effectively assemble the requisite components and control their properties remains an outstanding challenge. Our research group has recently developed a bioinspired synthetic methodology for interfacing polymeric surface coatings to (semi)conducting surfaces. The surface-grafted polymer chains provide: 1) a protective coating for the underpinning surface, 2) appropriate functional groups to direct, template, and assemble molecular components, including catalysts, and 3) a stabilizing three-dimensional environment for catalysts embedded within the polymers. Incorporation of rational synthetic design principles affords further control over the activity of the hybrid assemblies. The reported constructs thus set the stage for an improved understanding of the nano-, meso-, and macro-scale structure−function relationships governing the optoelectronic and catalytic properties of surface-immobilized catalyst−polymer architectures.
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Polymeric Interfaces for Renewable Fuel Production
Rational design of soft-to-hard material interfaces offers new opportunities to control matter and energy across the nano- and meso-scales, thus providing a chemical strategy to tailor the structural and physical properties of surfaces with molecular level precision. In the context of energy transduction, interfacing molecular catalysts with solid-state substrates is a promising approach to developing hybrid materials for generating solar fuels. However, effective integration of the requisite components, while controlling their redox properties and stability, remains a major challenge. Taking inspiration from nature, where specific amino acid residues and soft-material coordination environments control the redox properties of metal centers in proteins during enzymatic catalysis, we show that thin-film polymer surface coatings provide a novel strategy for assembling human-engineered catalysts onto solid supports. This presentation describes recent results from our laboratory aimed at better understanding the electrochemical and optical properties of hydrogen production catalysts assembled onto polymer-modified electrode surfaces. The polymer immobilization method results in unique electronic and vibrational spectroscopic signals associated with the immobilized molecular species. In addition, the use of discrete polymer architectures, coupled with rational synthetic modifications to the catalyst’s ligand environment, affords control over the chemical stability and redox potentials of surface immobilized molecular complexes, spanning a ~250 mV range.
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- Award ID(s):
- 1653982
- PAR ID:
- 10082169
- Date Published:
- Journal Name:
- Materials Research Society symposia proceedings
- ISSN:
- 0272-9172
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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