RUI: Collaborative Research: An Engineering Design Approach for the Tandem Catalysis of Carbon Dioxide (CO2) using Nanoporous Bi-layer Structures

University Of Wisconsin-La Crosse, La Crosse WI

Investigators

Abstract

As electricity derived from renewable sources becomes cheaper, its use for driving commercially relevant chemical processes has become increasingly viable, leading the path towards a sustainable energy economy. The combined research team at Purdue and University of Wisconsin Lacrosse are designing new catalysts for the conversion of carbon dioxide (CO2) to value-added products such as ethylene at industrially relevant conversion rates. The team will use their specific expertise to engineer novel layered catalyst structures, allowing the resulting materials to be more robust, efficient, and faster for CO2 conversion. This collaborative project involving both undergraduate and graduate researchers will also impact a broad range of technologies related to renewable energy, transportation, and defense. The project will promote knowledge-sharing activities such as regular joint meetings, undergraduate research mentored closely by graduate students, and inclusion of research activities into the curriculum. The project will also involve participation of underrepresented groups in working with research-intensive universities with a focus on skill-building activities such as group presentations, and scientific writing. This project aims to develop porous bi-layer catalysts on gas-diffusion layer (GDL) substrates which can then be used inside gas-fed carbon dioxide (CO2) electrolyzers allowing conversion to valuable C2+ products such as ethylene, at industrially relevant rates. The guiding principle of the project rests on using the bi-layer structure to break CO2 reduction scaling relations by creating asymmetric reaction sites, allowing greater selectivity through a cascade approach than from a single material. The use of a GDL substrate enables the possibility of high-rate conversions not possible with traditional reactors. The project will identify the underlying factors that determine structure-property relationships of the composite bilayer-GDL heterostructure with a focus on controlling the pore size, grain size, and associated grain boundary density. Specific metal/metal oxide heterostructures will be chosen based on recently available theoretical predictions in order to reduce the reaction overpotential, which often limits the energetic efficiency. In parallel, a carefully controlled pore size will be used to promote C-C coupling reactions through nano-confinement effects. This bilayer-GDL composite structure represents a unique combination of design elements, arising from two unique skill sets in catalyst fabrication and electrochemical testing. Coupled with a novel flow-reactor, the methodology promises to provide valuable insight into the challenging problem of high rate CO2 conversion to C2+ products such as ethylene. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.